A Comparison of Partial Cut and Clearcut Harvesting Productivity and Cost
in Old Cedar-Hemlock Forests in East Central British Columbia

Chad Renzie
BSc, University of Northern British Columbia, 2000

Thesis Submitted in Partial Fulfillment Of
The Requirements For the Degree Of
Master Of Scienee
in
Natural Resources and Environmental Studies

The University of Northern British Columbia
April 2006

© Chad Renzie, 2006

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ABSTRACT
Although clearcutting has been a historically dominant harvesting method in British
Columbia (representing 95% o f the total volume harvested annually), forest managers are
increasingly recommending the use of alternative silvicultural systems and harvest methods,
including various types o f partial cutting, to meet ecological and social objectives. In this
study we compared harvesting productivity and costs between treatments in 300-350 year-old
Interior Cedar-Hemlock stands. This was achieved through detailed and shift level time
studies. Residual stand damage was also assessed and recommendations for improving
operational planning/layout and the implementation of clearcut and partial cutting
silvicultural prescriptions were made. Harvesting costs varied in the ground-based clearcut
treatments from $10.95/m^ - $15.96/m^ and $16.09/m^ - $16.93/m^ in the group selection
treatments. The ground-based group retention treatment had a cost of $13.39/m^, while the
cable clearcut had a cost of $ 15.70/m^. An understanding of the traditional and alternative
products that can be derived from the harvested timber was imperative to increasing the
amount of merchantable volume and reducing the corresponding harvesting costs. Stand
damage was greatest in the group selection treatments; however mechanized felling showed
an increase in stand damage over manual felling while grapple skidding showed a decrease in
skidding damage compared to line skidding.

TABLE OF CONTENTS
ABSTRACT............................................................................................................................ II
TABLE OF CONTENTS.................................................................................................... Ill
LIST OF TABLES................................................................................................................VI
LIST OF FIGURES.......................................................................................................... VIII
ACKNOWLEDGEMENTS................................................................................................ IX
1

INTRODUCTION............................................................................................................ I

2

OBJECTIVES.................................................................................................................. 4

3

LITERATURE REVIEW............................................................................................... 5
3.1
3.2
3.3
3.3.1
3.3.2
3.4
3.5

4

Planning and Layout........................................................................................ 5
Felling................................................................................................................ 6
Primary Transportation.................................................................................. 8
Skidding............................................................................................................. 8
Cable Yarding.................................................................................................... 9
Loading and Processing................................................................................. 10
Stand Damage................................................................................................. 11

METHODS..................................................................................................................... 13
4.1
4.1.1
4.1.2
4.1.3
4.2
4.2.1
4.2.2
4.3
4.3.1
4.3.2
4.3.3
4.4
4.4.1
4.4.2

Harvesting System Descriptionand Specification.........................................13
Conventional System........................................................................................14
Semi Mechanized System................................................................................ 14
Cable System.....................................................................................................15
Study Sites....................................................................................................... 15
East Twin......................................................................................................... 16
Minnow............................................................................................................ 18
Study Techniques........................................................................................... 19
Shift Level Studies...........................................................................................20
Detailed Time Studies......................................................................................21
Activity Sampling.............................................................................................21
Specific Methods............................................................................................. 22
Objective 1 - Determ ine planning/layout cost fo r partial cut and clearcut blocks
22
Objective 2 Compare production rates (m^/hr)and cost ($/m^) fo r various silvicultural
prescriptions using ground-based and cable harvesting system s .................................... 23
4.4.2.1
Production Rates and Cost per Unit Volume Calculations...................... 23
4.4.2.2
Standardization and Sensitivity Analysis...................................................26
4.4.3 Objective 3 - Derive harvesting production prediction models based on appropriate
independent variables ............................................................................................. 27
.............................

-

111

4.4.4
5

Objective 4 - Quantify residual stand damagefor the different partial cuttingprescription
blocks........................................................................................................................ 28

RESULTS AND DISCUSSIONS.......................................................................................31
5.1
East T w in ............................................................................................................. 31
5.1.1 Planning and Layout........................................................................................... 31
5.1.2 Harvesting Operations........................................................................................ 32
5.1.2.1
Felling........................................................................................................... 32
5.1.2.2
Primary Transportation................................................................................ 35
5.1.2.2.1 Skidding.................................................................................................. 35
5.1.2.2.2 Yarding................................................................................................... 39
5.1.2.3
Manual processing....................................................................................... 43
5.1.2.4
Decking......................................................................................................... 45
5.1.2.5
Other Harvesting Costs................................................................................ 46
5.1.3 Summary o f Harvesting Costs............................................................................ 47
5.1.4 Landing A ctivity...................................................................................................49
5.1.5 Stand Damage....................................................................................................... 50
5.2
Minnow C re e k .....................................................................................................52
5.2.1 Planning and Layout............................................................................................52
5.2.2 Harvesting Operations.........................................................................................53
5.2.2.1
Felling........................................................................................................... 53
5.2.2.2 Skidding........................................................................................................ 56
5.2.2.3
Hoe Chucking...............................................................................................59
5.2.2.4 Processing..................................................................................................... 60
5.2.2.5
Loading......................................................................................................... 62
5.2.2.6 Other Harvesting Costs................................................................................ 63
5.2.3 Summary o f Harvesting Costs............................................................................ 64
5.2.4 Landing Activity................................................................................................... 66
5.2.5 Stand Damage....................................................................................................... 67
5.3
G eneral Discussion..............................................................................................70
5.3.1 Planning and layout............................................................................................. 70
5.3.2 Felling.................................................................................................................... 71
5.3.3 Primary Transportation.......................................................................................73
5.3.3.1
Skidding........................................................................................................ 73
5.3.3.2 Y arding......................................................................................................... 75
5.3.4 Processing..............................................................................................................76
5.3.5 Loading.................................................................................................................. 78
5.3.6 Summary o f Harvesting Costs............................................................................ 79
5.3.7 Stand Damage....................................................................................................... 81
5.3.8 Operational Implications.....................................................................................82
5.3.9 Suggestions fo r Future Harvesting Operations................................................85
5.3.10 Opportunities fo r Future Research.................................................................... 86

6

CO NCLUSION.................................................................................................................... 87

7

LITERATURE C IT E D .......................................................................................................89

IV

8 GLOSSARY OF HARVESTING TERMS................................................................... 95
APPENDICIES..................................................................................................................... 99

LIST OF TABLES
Table 1 Components of harvest systems, designation and description.................................... 13
Table 2 Harvesting treatment descriptions for East Twin and Minnow sites..........................17
Table 3 East Twin site and stand description............................................................................. 17
Table 4 Minnow site and stand description............................................................................... 19
Table 5 Summary of East Twin planning and layout costs......................................................32
Table 6 Summary of East Twin felling cycle times.................................................................. 33
Table 7 East Twin felling productivity and cost....................................................................... 33
Table 8 Significance of East Twin independent felling variables to total productive cycle
tim e............................................................................................................................. 34
Table 9 Significance of East Twin cable unit independent felling variables to total
productive cycle tim e.................................................................................................35
Table 10 Summary of East Twin ground-based skidding cycle tim e...................................... 36
Table 11 East Twin skidding productivity and cost.................................................................. 37
Table 12 Significance of East Twin independent skidding variables to total productive cycle
tim e............................................................................................................................. 39
Table 13 Summary of East Twin yarding cycle tim e............................................................... 40
Table 14 East Twin yarding productivity and cost................................................................... 40
Table 15 Significance of East Twin independent yarding variables to total productive cycle
tim e............................................................................................................................. 42
Table 16 East Twin shift level summary for manual processing............................................. 43
Table 17 East Twin species volumes for each treatment'.........................................................43
Table 18 East Twin shift level summary for loading.............................................................. 46
Table 19 Summary of East Twin equipment moving costs......................................................46
Table 20 Summary of East Twin skid trail and landing construction costs............................ 47
Table 21 Summary of East Twin total costs ( $ W ) '................................................................. 48
Table 22 Summary of East Twin total costs ($/m^) at a standardized merchantable volume
per stem of Im^ ' .......................................................................................................49
Table 23 Summary of East Twin landing activity sampling.....................................................50
Table 24 Stand damage summary for East Twin group selection treatment.......................... 51
Table 25 Summary of Minnow planning and layout costs.......................................................52
Table 26 Cycle time o f Minnow mechanized felling phase.....................................................54
Tahle 27 Summary of Minnow mechanized felling costs........................................................54
Tahle 28 Significance of Minnow independent felling variables to total productive cycle
tim e............................................................................................................................. 54
Table 29 Summary of Minnow manual felling costs................................................................ 55
Table 30 Cycle time o f Miimow ground-based skidding phase.............................................. 56
Table 31 Summary of Minnow skidding production and costs................................................57
Table 32 Significance of Minnow independent skidding variables to total productive cycle
tim e............................................................................................................................. 59
Table 33 Minnow shift level summary for hoe chucking.......................................................... 60
Table 34 Minnow shift level summary for manual proeessing.................................................61
Table 35 Minnow species volumes for each treatm ent'........................................................... 61
Table 36 Minnow shift level summary for loading.................................................................. 62
Table 37 Summary of Minnow Twin equipment moving costs.............................................. 63

VI

Table 38 Summary of Minnow skid trail and landing construction costs...............................64
Table 39 Summary o f Minnow total costs ($/m^)^................................................................... 64
Table 40 Summary o f Minnow total costs ($/m^) given a standardized merchantable volume
per stem of Im^ *....................................................................................................... 66
Table 41 Summary of Minnow landing activity sampling.......................................................67
Table 42 Minnow stand damage summary................................................................................ 69
Table 43 Planning and layout costs per hectare^.......................................................................70
Table 44 Skidding costs given a standardized skidding distance of 100 meters and
merchantable volume per stem of Im^ ^.................................................................. 75

V ll

LIST OF FIGURES
Figure 1 Relationship between total productive cycle time for felling and tree diameter for
the East Twin cable treatment................................................................................. 35
Figure 2 Summary of East Twin non-productive timing elements for skidding.................... 38
Figure 3 Productive cycle time distribution for East Twin cable yarding.............................. 41
Figure 4 Non-productive cycle time distribution for East Twin cable yarding...................... 42
Figure 5 Summary o f Minnow non-productive timing elements for skidding....................... 58
Figure 6 Sensitivity analysis of planning and layout costs versus merchantable volume per
tree................................................................................................................................71
Figure 7 Sensitivity analysis o f observed felling costs versus merchantable volume per tree
......................................................................................................................................72
Figure 8 Sensitivity analysis of skidding costs versus merchantable volume per tree...........74
Figure 9 Sensitivity analysis of clearcut yarding and skidding costs versus merchantable
volume per tre e .......................................................................................................... 76
Figure 10 Sensitivity analysis of processing costs versus merchantable volume per tree
77
Figure 11 Pocket and ring rot in western red cedar.................................................................. 78
Figure 12 Sensitivity analysis of loading costs versus merchantable volume per tree...........79
Figure 13 Sensitivity analysis of total harvesting costs versus merchantable volume per tree
80

V lll

ACKNOWLEDGEMENTS
The author wishes to acknowledge Forest Engineering Research Institute of Canada (FERIC)
for providing technical assistance and a detailed timing program used in the study. Special
thanks are also extended to the logging contractors and the staff of the Robson Valley Forest
District for their cooperation. The author would also like to thank Dan Mathews and Rob
Bourcier for their assistance with the fieldwork. This project was funded in partial by the
Robson Valley Enhanced Forest Management Pilot Program (EFMPP). The author’s sincere
thanks go to Mike lull for inviting him to participate in the silvicultural systems trial project.
The guidance o f Han-Sup Han and Joselito Arocena has been essential to the author’s
success and he wishes to deeply thank them both.

IX

1 Introduction
In the past, forest management in coastal and interior cedar hemlock forests stands tend to
focus on the conversion of forests to even-aged second-growth forests through clearcut
harvesting. However, forest resource managers have begun to prescribe a wide range of
stand structures, age structures, and species compositions, to meet an increasing array of
ecological, social, and silvicultural objectives (Weetman, 1996; Amott and Beese, 1997;
Kohm and Franklin, 1997; lull et ah, 1998). These include various silvicultural strategies,
from smaller openings, dispersed partial cuts, and variable retention systems. Managing for
non-timber resources is especially important in the Columbia trench between Prince George
and McBride, British Columbia (BC), because of the pressure to preserve mountain caribou
{Rangifer tarandus-caribou (Linnaeus)) habitat and a tourism industry (Jull et ah, 2002,
Moon et ah, 2004). Improved knowledge regarding the implementation of alternative
silvicultural methods is imperative to meet these demands, including productivity and cost.

The costs involved with various alternative silvicultural methods in western red cedar {Thuja
plicata Donn ex D. Don) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) forests,
specifically the interior cedar hemlock (ICH) stands, in BC are poorly understood. There is
limited knowledge on harvest productivity and cost in partial cutting these stands is due to
the low market value of the ICH stands during the early 1980’s (Mandzak et ah, 1983;
Sinclair, 1984) and the perception that only clearcut harvesting was financially viable. The
Northern Rockies ICH/Silvicultural Systems Project was established to examine ways of
managing ICH forests in a manner that would address both ecological and socio-economic
concerns (Jull et ah, 2002). This project investigates the effects of various partial cutting

regimes on short-term and long-term stand growth and development, loss and creation of
stand structural biodiversity attributes (wildlife trees and course woody debris), windthrow,
regeneration, and tree mortality. The research projects address a wide variety of issues
including: 1) short-term and long-term growing stock development, stand productivity, stand
structural development, species composition, logging and wind damage and mortality; and 2)
short-term and long-term processes of loss and creation of structural biodiversity attributes,
specifically wildlife trees and coarse woody debris. As part of this study, a harvesting
productivity and cost analysis of partial cutting versus clearcutting was conducted, this
complements the long term goals by providing an economic and operational perspective. A
harvesting research team at the University of Northern British Columbia (UNBC) in
cooperation with the Ministry of Forests Small Business Enterprise Forestry Program
monitored harvesting activities in the two study sites: East Twin and Minnow Creek, located
near McBride, BC.

Although literature about partial cutting, any silvicultural system that remove selected trees
and leave desirable trees for various stand objectives, is abundant for coastal BC (Moore,
1991; Daigle, 1995; Bennett, 1997), past research efforts concerning the costs of partial
cutting of ICH stands in central BC have been minimal. The forest management objectives,
stand structures, harvesting conditions in the interior BC are quite different from those of
coastal BC.

In a second growth cedar hemlock stand near Kispiox, BC, it was found that the cost of a
conventional harvesting system in a partial cut was 1.98 times higher than that of a

conventional clearcut (Thibodeau et al., 1996). Two studies in old growth ICH stands near
Revelstoke ( BC), found that harvesting costs to be 1.1 to 1.4 times higher than that of a
clearcut (Walters, 1997a; Walters, 2001). A cable skyline system partial cut in a cedar
dominant stand in east central BC, costs 3.77 times higher than a conventional ground-based
clearcut (Pavel, 1999).

2

Objectives

The broad goal of this study was to determine the production rates, costs, and residual stand
damage of partial harvesting systems in ICH stands. Improved knowledge regarding the
costs of implementing alternative silvicultural methods is imperative for forest managers to
meet non-timber values of the area while meeting the demand for cedar products. This study
was done for three different levels of tree removal treatments in the ICH. The specific
objectives are:

1. Determine planning/layout cost for partial cut and clearcut blocks;
2. Compare production rates (m^/hr) and cost ($/m^) for various silvicultural
prescriptions using ground-based and cable harvesting systems;
3. Derive harvest production prediction models based on appropriate independent
variables; and
4. Quantify residual stand damage for the different partial cutting prescription blocks.

3

Literature Review

3.1

Planning and Layout

Planning and layout in timber harvesting operations is key to the suceess of an efficient
harvesting operation and reduces environmental impacts. The layout costs in group selection
and retention units for interior cedar dominant stands are 1.9 to 4 times that of clearcut units
(Thibodeau et ah, 1996; Walters, 1996; Walters, 1997a; Walters, 2001). This is similar to
other interior forest types in Canada and the United States where partial cut layout costs
ranged from 2.4 to 6.3 times that of clearcut units (Kellogg et ah, 1991; Kellogg et ah, 1996;
Dunham, 2001, 2004; Sambo, 2003). This higher cost of partial cutting than clearcutting is
the result of more intensive timber cruising, the creation of internal patch cut layout
boundaries, increased tree marking, and the need for designed skid trail networks through the
residual stand that allows for multiple entries (Thibodeau et ah, 1996; Walters, 1996;
Walters, 1997a; Walters, 2001).

Harvest design plans consider many factors including the optimal spacing of yarding
corridors, haul roads, skid trails, and landings (Pavel, 1999). Optimal spacing models
determine the best spacing based upon equipment and stand charaeteristies (MeNeel and
Young, 1994; Howard et ah, 1996; Rutherford, 1996). While cost savings may be achieved
through optimal spacing, the benefits must be compared with the impacts on the other
management goals (Pavel, 1999). Regardless of optimal spacing, in ground-based units, the
orientation of openings and extraction network should be designed and oriented to facilitate
enhanced felling and skidding productivity. Patch openings should be designed to “funnel”
trees in the direction of the skid trail. This funnelling can result in improved skidding /

yarding and felling productivity while reducing residual stand damage (Bennett, 1993;
Thibodeau et ah, 1996; Kosicki, 2000a).

Timber cruising for partial cut units is time consuming because of the required two-measure
plots per hectare versus one measure-plot and one count-plot per hectare in clearcut units
(BC Ministry Forests, 1996a). This requirement increases layout cost, but high quality field
layout is regarded as crucial to an efficient partial cutting operation and as a result should
remain a high priority (Bruno, 1979; Hedin, 1994; Thibodeau et ah, 1996).

Tree marking increases layout costs though allows fellers to be free from selecting trees to be
felled, thus increasing their productivity (Kemmler, 2000). Marking reflects the objectives
set for the logging operation and establishes the height, species, and stand structure of the
remaining stand. Where directional felling is required and feasible, it is recommended that
the directions to be and not to be felled be marked on the tree (Aho et ah, 1983; Moore,
1991). Tree marking must consider the safety of the feller through a knowledge of
characteristics (i.e., lean, and distribution of branches) of individual and adjacent trees
(Moore, 1991; Walters, 1997a).

3.2

Felling

In both partial and clearcut harvesting, felling by mechanical means in the ICH in east central
BC resulted in cost savings from 40 to 50% compared to manual felling (Thibodeau et ah,
1996). Mechanical felling has a proportionally higher production rate (m^/hour) over
increased ownership and operating costs. Besides cost, advantages of mechanized felling

compared to manual felling include better worker safety, better control of stems to reduce
breakage and residual tree damage and improved skidding efficiency through tree bunching
(Kluender and Stokes, 1994; Thibodeau et al., 1996; Parker, 2002). Advantages of manual
felling include no constraints on slope and tree sizes. However, when felling trees using a
chainsaw, stumps should be close to the ground and on an angle to minimize hang-ups
(Pavel, 1999; Han and Renzie, 2005).

Where manual felling is required, the primary concern of the teller must be safety (Moore,
1991; Parker, 2002). The feller must take into consideration the kick back potential of the
chainsaw, assess the trees for possible hazards (i.e., loose branches that may dislodge when
falling), and have an escape route ready in case the tree does not fall as planned. Felling
productivity is also affected by environmental conditions. In colder climates, felling
efficiency declines because the wood becomes harder to cut when it is frozen (Mitchell,
2000 ).

The manual felling costs in 60% volume removal treatments (group retention) in the ICH are
1.2 times more expensive than those in clearcuts as the result of directional felling
requirements (Thibodeau et al., 1996). While treatment can affect the felling cost,
merchantable volume per stem often has a larger effect on the total cost (Ashe, 1916;
Lynford, 1934; Mann and Mifflin, 1979; Kluender et al., 1997).

3.3

Primary Transportation

3.3.1 Skidding
The use of medium sized line and grapple skidders, commonly used for conventional or
mechanized harvests of clearcuts, in heavy removal partial cut operations is both cost
effective and efficient (Thibodeau et al., 1996). The use of horses, small crawler tractors
and/or harvester/forwarder systems were recommended for light removal partial cut systems,
as these machines or animals are easy to maneuver. Tree size and felling method may also
dictate skidding equipment and methods, in the case of large tree sizes where mechanical
felling may not be possible. Mechanical felling allows for the bunching of logs, making the
use of grapple skidders economically viable. When bunching is not possible, logs may be
more efficiently removed by a line skidder (Kluender and Stokes, 1994; Thibodeau et al.,
1996). The use of line skidders may be economical in a small scale operation at a lower
production rate as a lower capital investment is required compared to grapple skidders
(Kluender and Stokes, 1994). In addition, the use of line skidders promotes manual felling,
also reducing overall capital investment. The skidding cost per cubic meter, when using a
line skidder, in a 60 % removal treatment (group retention) is 1.85 times higher than a
clearcut (Thibodeau et al., 1996). The differences observed in costs are often due to
increased skidding cycle time, as much as 6%, in partial cut treatments compared to similar
clearcut units (Krag, 1992). Skidding productivity is also affected by weather, skidding
distance and slope (Mitchell, 2000). In a uniform stand, the greater the slope and skidding
distance, the less productive the skidder becomes as the cycle time to retrieve a turn of logs
increases while the volume of the turn remains fairly constant.

3.3.2

Cable Yarding

Uphill yarding is most efficient when yarders with slack-pulling carriages and chokers are
utilized in either a single or multi-span skyline system (MacDonald, 1999). For downhill
yarding, a running skyline system is required as the haulback line allows for the carriage to
return uphill and provides better control of the carriage and payload when traveling downhill
(Gardner, 1980; Bennett, 1997; MacDonald, 1999; Dunham and Gillies, 2000). While a
running skyline system can be used in partial cuts, it is more popular in clearcuts and often is
used with a mobile backspar. Advantages of single span systems in both partial and clearcuts
are generally limited to higher production and thus reduces costs due to lower yarding
corridor change times (Howard et al, 1996). Multi-span systems can be advantageous
especially where required road can be reduced; it improves deflection, increases payload,
shortens the overall rigging time due to fewer yarding corridors to access similar volume of
wood, and reduces residual stand damage in partial cuts (Pavel, 1999). Clamping carriages
with chokers are beneficial in partial cutting as they allow for better lateral yarding. Lateral
yarding is critical in partial cut cable units to efficiently remove felled trees from the residual
timber along the yarding corridor and makes partial cutting a cost effective operation
(MacDonald, 1999). If timber is to be harvested as a strip surrounding the yarding corridor, a
slackpulling clamping carriage is not required as lateral yarding is not necessary.

Cable partial cutting costs ranged from 1.31 to 1.46 times more expensive than cable clearcut
units because residual trees in a partial cut increased time and cost for road changes (Bennett,
1997;Riggs et al., 1996). Differences in tree size, species composition and terrain
characteristics between the Coastal Western Hemlock (CWH) and ICH biogeoclimatic zones

render these results to be inaccurate for the interior of BC. A study in the interior of BC on a
cedar dominant stand stated that partial cutting was operationally feasible but failed to
provide any economic benefits (Walters, 1997b). Second growth partial cutting in the ICH
had yarding cost of $14.56/m^ while an old growth stand had a yarding cost of $12.1 i W
(Pavel, 1999; Dunham and Gillies, 2000). No published results exist for clearcut yarding in
the ICH.

3.4

Loading and Processing

Effective utilization of the loader is essential to ensure that the landing is clear and safe and
that trucks are loaded with a minimum delay (Pavel, 1999). In the interior of BC, common
loading equipment includes both front-end loaders (wheel based) and hydraulic loaders (track
based). Front-end loaders are limited to relatively fiat large landings. Wheel loaders also
travel faster than hydraulic loaders on flat ground, this allows for sorting to be less restricted
than with a hydraulic loader, provided landing space is not restricted. A butt ‘n top loader
effectively handles small-diameter trees while heel boom loaders are suited to confined areas
but the ability to sort large timber is restricted by the number of logs that can be piled within
an area immediately adjacent to the loader (MacDonald, 1999).

Processing methods are largely determined by harvesting method or by tree size
characteristics. Mechanical processing has greater production than manual processing but
requires greater capital investments (MacDonald, 1999). Where tree size restricts
mechanical processing, manual processing is used. Manual processing is generally

10

completed on the landing or roadside and therefore requires the bucker and machine operator
be aware of each other’s presence for safety reasons and to reduce the risk of accidents.

The loading cost for partial cutting is currently unavailable in the ICH, however, in the
CWH, the loading cost per cubic meter in partial cuts ranges from 1.31 to 1.46 times greater
than clearcut units due to greater non-productive delays in the partial cut units (Bennett,
1997). The loader waited for wood to process longer in the partial cut units than the clearcut
due to the longer yarder cycle times (Bennet, 1997).

3.5

Stand Damage

When assessing stand damage, many sampling methods can be used. These sampling
methods include random plot sampling, systematic transect, blocks along yarding or
skidding corridors, systematic plot sampling, and sampling each tree in a unit (Han and
Kellogg, 2000). The most efficient method of sampling is systematic plot sampling (Han and
Kellogg, 2000). Trees may not be considered acceptable as a residual crop tree if they
exceed any of the following thresholds (Pavel, 1999):
•
•
•
•

A wound that girdles 1/3 of the stem circumference
A wound on a supporting root
A gouge in the stem
A wound exceeding 400 cm^ on the stem

Damage in skyline partial cutting in the ICH was 5.4% of the stand with 2.4% considered
unacceptable for residual crop trees (Pavel, 1999). In coastal skyline partial cuts, damage
rates were significantly higher, up to 10% of the residual stand, and may have been the result
of the crews being inexperienced with partial cutting (Bennett, 1997; Boswell, 2001). When

11

the yarder’s running lines were too low, the ineidenee of tree scaring increased due to a lack
of controlling turns (Bennett, 1997). A reduction in stand damage can be achieved through
good carriage control when passing through intermediate supports and precise carriage
positioning when beginning lateral yarding (Pavel, 1999).

The majority of stem damage is located on hauling roads and yarding corridors where the
most harvesting activity occurs (Bennett, 1997; Pavel, 1999; Han and Kellogg, 2000). In
ground-based partial cuts, the orientation of harvest units and directional felling play an
important role in reducing stand damage. Skid trails should be aligned as straight as possible
to reduce possible stand damage. To reduce stand damage on skid trails, the use of rub trees,
protective culverts or higher stumps on the edge of skid trails are also recommended
(Bennett, 1993; Matzka, 1998; Kosicki, 2000a). These rub trees are then carefully removed
once harvesting is completed. Motivated operators can also result in less residual stand
damage (Langeson, 1997). This can be implemented through a bonus/penalty system
(McNeel and Dodd, 1996). In the case of partial cutting, it is expected that 5 to 10% of the
residual stand may be lost to logging damage (Smith and Lamson, 1982).

12

4

Methods

4.1

Harvesting System Description and Specification

The choice of harvesting systems was based on stand and terrain characteristics including
slope constraints, tree sizes and common local harvesting systems. The systems selected for
the harvesting process were conventional, semi-mechanized, and cable (Table 1). Pictures of
equipment utilized on each of the study sites are in Appendices 1 and 2.

Table I Components of harvest systems, designation and description
Felling
Operation

Primary Transportation

Landing Operation

Conventional

Manual felling

Rubber-tired skidder
equipped with a winch
line

Wheel log loader
Manual processing

Cable

Manual felling

Tower yarder, using a
running skyline system

Track log loader
(Heel boom).
Manual processing

Manual felling
Rubber-tired skidder
and feller
equipped with a grapple
buncher.

Wheel log loader.
Manual processing

Harvest System
East Twin Creek

Minnow Creek
Semi-mechanized

Manual Felling was utilized in all three harvest systems. A high degree of butt flare in cedar
in combination with butt rot made directional felling difficult and at times dangerous.
Manually felled trees were generally felled in a downhill direction as the trees were leaning
and weighted by branches to fall in that direction. Where tree conditions did not permit, the
trees were felled in another safe direction. During manual felling, approximately 1 meter of
snow was present, however shovelling around the base of the tree was not required for the
majority of trees, as most stems were free of snow at cut height and the snow did not hinder
the feller’s movement. Mechanical felling was only used in the semi-mechanized harvest

13

system. Primary transportation methods varied between the three harvesting systems,
utilizing a yarder, line skidder, and grapple skidder. Manual processing (delimbing and
bucking) at the landing was utilized as tree size and defect characteristics prohibited
mechanized processing. Loading was done during and immediately after harvesting. Other
primary duties of the loader included sorting timber on the landing, assisting the bucker by
separating timber, clearing processed timber, and clearing slash and waste from landing to
promote bucker safety.

4.1.1

Conventional System

The conventional system is a ground-based system that utilized manual felling. Timber was
felled in a bunched manner, when possible, allowing for more trees to be choked at once.
Wheel based skidders with a winch line extracted logs from the stand to the landings. A
conventional system is typically used for terrain that has a sustained slope of < 35%. Manual
processing and loading, using a wheel based front end loader, occurred at the landing. Due
to time of harvest, logs at certain landings were decked until the spring time when road
weight restrictions (<70% of the legal weight) were lifted.

4.1.2 Semi Mechanized System
The semi mechanized system was a ground-based system that is suitable for terrain that has a
sustained slope of < 35%. Mechanized (feller buncher) and manual felling methods were
utilized depending on tree size and characteristics such as defect levels and species. Large
cedar trees were mechanically felled through multiple cuts and pushed by a feller buncher, as
a result of being hollow or rotten in the center. Large spruce were not felled using the same
methods as the spruce was solid and the multiple cuts and pushing required would have

14

resulted in unnecessary stump pull and butt shatter. A wheel-based skidder with a grapple
was used to extract logs from the stand to the landings. The use of a feller buncher allowed
felled trees to be bunched or grouped prior to skidding to improve the efficiency of the
grapple skidder. As a grapple skidder was used to transport the timber, the trees were felled
in a fashion that the butts faced the skidding direction, wedging the timber into the grapple
when dragged. Trees tend to slide free from the grapple or required greater grapple
pressures, resulting in increased breakage, when skidded from the top. Hoe chucking was
utilized to orient and group the logs butt first for grapple skidding in steeper locations.
Manual processing and loading, with a wheel based front end loader, at the landing was
utilized. Logs were decked on the landing only until trucking was arranged.

4.1.3

Cable System

A cable system was utilized where slopes were > 35%. Manual felling was implemented due
to large tree sizes and steep terrain. A tower yarder using a running skyline system was
utilized and trees were felled downhill and manually processed. Yarding was accomplished
by partially suspending the logs to avoid hanging up on the remaining stumps and slash.
Partial suspension was accomplished by pulling the mainline in while dragging the haulback
brake. Manually processed logs were decked with a track based heal-boom until spring road
weight restrictions were lifted.

4.2

Study Sites

The study consisted of two harvest areas located between 32 and 35 km west of the town of
McBride in the Rocky Mountain Trench in central British Columbia, and was part of the

15

Northern Rockies ICH / Silvicultural Systems Project (Jull et al., 2002). The study areas
located at East Twin Creek and Minnow Creek, referred to as East Twin and Minnow from
here on, are dominated by western red cedar with components of subalpine fir (Abies
lasiocarpa (Hook.) Nutt.), Engelmann spruce (Picea engelmanii Parry ex Engelm.), and
western hemlock. Both sites are located in the Goat River Wet Cool ICHwkS, a wet cool
variant of the interior cedar hemlock biogeoclimatic zone (DeLong et al, 1994; BC Ministry
of Forests, 1996b; 1996c).

4.2.1

East Twin

The East Twin study area is located 35 km west of McBride, BC on the north-eastern side of
the Fraser River (53° 30' N, 120° 20' W). The East Twin drainage is a relatively narrow,
generally steep-sided valley running perpendicular to the Rocky Mountain Trench. This area
is located between 1.5 km and 3.5 km on the East Twin Forest Service Road, branching from
7.3 km on the Mountainview Forest Service Road. The study area is 950 to 1050 meters
above sea level (msal) and has a northwest aspect. Two harvesting systems, cable and
ground-based, were used to harvest two separate treatment units (Appendix 3). The cable
harvesting system was utilized on the steepest part (>35% slope) of the 100 % removal
treatment while the remainder, 1.1 hectares, of the 100% removal treatments and entire group
selection treatment (30% removal treatment) were harvested by a ground-based conventional
system. In the group selection treatment, average harvest patches of 0.2 hectares in size were
laid out (Table 2) with a skid trail system that would allow for multiple entries.

16

Table 2 Harvesting treatment deseriptions for East Twin and Minnow sites
Study area

Treatment

East Twin

Group selection
(30% removal)
Clearcut
(100% removal)
Clearcut
(100% removal)

Minnow

Group selection
(30% removal)
Group retention)
(70% removal)
Clearcut
(100% removal)

Harvest system

Treatment
area (ha.)

Size of internal harvest
groups / leave patches
0.1-0.3 ha. harvest groups;
Average = 0.2 ha.

Ground-based

8.7

Ground-based

1.1

N/A

Cable

6.7

N/A

Ground-based

11.2

Ground-based

10.7

Ground-based

7.4

0.1-0.3 ha. harvest groups;
Average = 0.2 ha
0.1-0.3 ha. leave patches;
Average = 0.2 ha

N/A

Table 3 East Twin site and stand description
Silvicultural treatment
Elevation Range (m)
Aspect
Treatment size (ha)
Harvested area (ha)
Previously harvested area (ha)
Slope (avg.)
Species (%)“*
Western red cedar
Subalpine fir
Engelmann spruce
Western hemlock

Group selection
ground-based
9 0 0 - 1050
NW
8.7
2.1
0
0-50% (20%)

Clearcut ground-based
9 0 0 - 1050
NW
1.1
1.1
0
0-30% (15%)

Clearcut cable
900 - 1050
NW
6.7
6.7
0
30-130% (55%)

86.6
3.4
10.0
0.0

79.1
9.3
5.6
6.0

902
2.8
22
4.8

Stems/ha ®
404.7
424.3
424.3
Avg. DBH (cm)®
53.2
562
532
Avg. ht (m)®
36.7
33 j
332
Gross vol. (m^/ha)®
1074.6
908.0
908.0
Net merchantable vol (m^/ha)*’
349.0
441.6
433.0
“ Provided by the BC MOF Cruise report.
Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF

17

4.2.2 Minnow
The Minnow study area is located 32 km west of McBride, BC on the north-eastern side of
the Fraser River (53° 28' N, 120° 1S' W), just south of the East Twin drainage system. This
area is located 3 km on the Minnow Creek Forest Service Road, branching from 5.5 km of
the Mountainview Forest Service Road. The study area is 1050 to 1200 masl and has a
southwest aspect. The site was harvested using a semi-mechanized system with 30 %, 70 %
and 100 % tree removal in group selection, group retention and clearcut treatments
(Appendix 3). The primary goal of the layout in the group retention treatment was to ensure
that all of the harvested area was about two tree lengths to a retention patch or and
unharvested block boundary. The removal patches in the group selection treatment had an
average size of 0.2 hectares and the group retention treatment had leave patches of - 0.2
hectares.

18

Table 4 Minnow site and stand description
Silvicultural treatment

Group selection

Group retention

Clearcut

Elevation Range (m)
Aspect

1050- 1200
SW

1050- 1200
SW

1050- 1200
SW

11.2
0.2

10.7
1.5

7.4

3.6
0-50% (30%)

6.1

7.4
0-40 (30%)

Treatment size (ha)
Previously harvested area (ha)
Harvested area (ha)
Slope (avg.)
Species (%)®
Western red cedar
Subalpine fir
Engelmann spruce
Western hemlock

60.4
19.4
18.3
1.9

0-30% (15%)

0.0

46.5
2T3
24.6
1.6

75.0
11.4
13.0
0.3

394
Stems/ha ®
288
349
4&2
Average DBH (cm)^
47.1
44.7
26.0
Average height (m)“
25.4
219
1122.1
659.4
Gross vol. (m^/ha)“
819.8
359.2
Net merchantable vol (m^/ha) ^
308.8
367.6
Provided by the BC MOF Cruise report.
*’Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF

4.3

Study Techniques

A field-based, observational study was eonducted to evaluate the effect of various
silvicultural prescriptions on harvesting productivity and cost in the ICH stands. Replication
and modification of treatments and harvesting systems was not possible due to time and cost
constraints. Comparison of costs among alternative logging systems requires accurate
production data. The collection of this data was difficult due to the variations in the logging
environment (Olsen and Kellogg, 1983). To successfully calculate the productive and non­
productive time, detailed time studies were conducted. This data was then used to determine
the cycle element durations, and calculate interactions between equipment, personnel, and

19

harvesting attributes. The methods used for timing included shift level studies, detailed time
studies, and activity sampling on landing areas.

4.3.1

Shift Level Studies

Shift level studies are daily production averages based on a worker’s record of pieces
handled per unit work time (Olsen and Kellogg, 1983; Olsen et al., 1998). In this study,
cooperation was requested from each equipment operator and other key personnel to collect
accurate production information at the end of every shift. The following information was
collected from equipment operators and ground personnel on a daily basis (only information
pertinent to an individual position was requested):
Date
Unit# (for removal patches)
Treatment area(s)
Operator(s) name(s)
Weather conditions
Equipment description or number
Shift length and break times
Non-productive time (>10 minutes and reason for delay)
Pieces handled (trees, logs, tops, etc.)
# of cycles (i.e. turns skidded or yarded, or trees felled)
General comments outlining the day’s production

To ensure reliability in cycle and piece numbers, equipment operator and ground personnel
used mechanical counting devices (tally counters) for keeping track of log and cycle counts.
In addition, when changing treatments, an additional shift level form was filled out. The shift
level forms were collected at least biweekly and daily when possible to ensure that the forms
were being completed properly (Appendix 4). In addition, since all of the operators were
paid on an hourly basis and not on productivity, there was little incentive for them to bias the
data

20

4.3.2

Detailed Time Studies

A handheld computer (Ranger 9600) was used for detailed time studies. Time and conditions
required for each turn were recorded. A turn is described as the sequence of work elements
required to bring a group of logs or trees to the landing. Detailed timing includes the cycle
element timing for each phase of harvesting (felling, skidding, and yarding) and recording of
delay descriptions. Both independent variables (slope, turn size, etc) and detailed time data
(dependent variables), were collected (Appendix 5). Detailed timing data was conducted by
two researchers at each site. A standard training program ensured both researchers collected
data using the same techniques and methods. In addition, each researcher timed only one
harvesting component, skidding / yarding or felling, but not both. Manual felling, line
skidding, and yarding was timed in East Twin, while only mechanized felling and grapple
skidding was timed in Minnow due to limitations in funding and manpower. In the East
Twin clearcut unit, tree diameter at cut height data was collected. This data was not collected
in the other East Twin and Minnow treatments due to safety concerns and manpower
constraints.

4.3.3 Activity Sampling
Activity sampling measures the proportion of the workday spent on a series of activities by
individual machines and people (Matzka, 1998). Activity sampling also measured the
interactions of equipment and personnel at the landing. Observations may be made at
random times or at equally spaced intervals. If at equally spaced intervals they are called
fixed-interval, systematic, group timing, or multi-moment sampling (Olsen and Kellogg,
1983; Olsen et al., 1998). An equally spaced time intervals method was chosen and set at 20

21

seconds for a minimum of an hour to ensure the accuracy of the data as recommended by
Olsen and Kellogg (1983). Each landing was sampled in the morning with a measurement
starting time o f 9:00AM t o l l :00AM.

4.4

Specific Methods

4.4.1

Objective 1 - Determine planning/layout cost fo r partial cut and clearcut blocks

The planning and layout costs were calculated by dividing the total cost of planning and
layout by the total volume removed for each treatment. The cost per unit volume were
determined for each treatment and site using volume data obtained from the BC Ministry of
Forests (BC MOF) along with person hours and corresponding hourly costs provided by
consultant and UNBC researchers. The volume information was provided by species and
treatment from the BC MOF from piece scale data. The final volume, not the raw data, by
treatment and species was only information provided as such no further analysis was
conducted on the data. The timber was scaled in aeeordanee with the BC MOF regulations
(BC Ministry Forests, 1995) by multiple scalers. The consultant was responsible for location
and marking of boundaries, office analysis of field data (cruise), and creation of maps.
Cruise data provided was also conducted in accordance with the BC MOF regulations (BC
Ministry Forests, 1996a). University researchers determined the location of skid trails and
residual and removal tree selection and marking. Data collected for calculating the planning
and layout costs included:

22

•
•
•
•

Date
Treatment area
Volume of timber harvested in each treatment.
Person hours spent by the crew in:
■ Location and marking of skid trails/boundary
■ Office analysis of field data (cruise) and creation of maps
■ Residual and removal tree selection and marking

Treatment planning and layout costs ($/m^) were calculated by dividing the total planning
and layout costs for each treatment by the provided BC MOF merchantable volume for that
treatment [1]. Hectare costs were calculated for both harvest and treatment area using the
same formula [2 ].
[1] Planning and layout costs ($/m^ - by treatment):
Planning and layout costs ($/m^) =

Total planning and layout costs-----BC MOF scaled volume (m^)

[2] Planning and layout costs ($/ha - by harvest or treatment area):
Planning and layout costs ($/ha) =

4.4.2

Total planning and layout costs------Harvest or treatment area (ha)

Objective 2 - Compare production rates (m^/hr) and cost ($/m^) fo r various
silvicultural prescriptions using ground-based and cable harvesting systems

The production rates and cost per unit volume for each treatment was determined through the
use of shift level and detailed time studies in combination with the provided BC MOF scaled
treatment volumes.

4.4.2.1 Production Rates and Cost per Unit Volume Calculations
The shift level and detailed time study was used to calculate the productive and non­
productive times in a cycle. The non-productive cycle time was calculated from hoth the

23

shift level (for larger delays > 1 0 minutes) and detailed time study (for small delays < 1 0
minutes). These delays were subtracted from the scheduled machine hours (SMH) for each
piece of equipment and used to calculate the effective or productive machine hours (PMH).
The average productive cycle time was calculated from the detailed time study information
(Appendices 8 to 10,12, and 13).
[3] Effective hour;
Effective hour (min/hr) = 60min x (1 - % delay time per scheduled machine hour, SMH)

[4] Cycles per hour:
Cvcles
Hour (SMH)

_

Effectivehour
(min/hr)_____
Average productive cycle time (min/tum)

Once cycle times were calculated, the volume associated with each cycle was determined [5]
along with the hourly production [6 ].
[5] Volume per cycle:
Cubic meters
Cycle

^

Merchantable volume (m^)
Piece

^

Pieces
Cycle

[6] Hourly production (m^/SMH):
Cubic meters
Hour (SMH)

=

Cvcle
Hour (SMH)

^

Cubic meters
Cycle

Individual machine cost was calculated using individual ownership and operating costs
(Lambert and Howard, 1990). The cost of ownership for each piece of equipment is based on
factors such as book price, interest rates, book salvage value, depreciation period, taxes, and
insurance. The operating costs include fuel and oil consumption, labour, and operating

24

supplies (Mifflin, 1980). Appendices 6 and 7 contain the machine rates for each machine
used in the study.

Production cost ($/m^) for each machine was calculated by dividing the production rate by
the appropriate machine ownership and operating costs (Lambert and Howard, 1990) [7]. As
all the machines involved in harvesting had different production rates, all of the productive
costs were determined independently from one another. The overall production cost of the
harvesting system was calculated by the summation of the productive costs for each machine
utilized (Lambert and Howard, 1990).
[7] Final harvesting cost (by equipment):
_______ $________
Cubic meters

^

Ownership & operating cost (S/SMH')
Hourly production (m^/SMH)

In the Minnow units, both manual felling and mechanized felling occurred. While the
observed costs could be determined using the previous formulas [3-7], the contribution of
each process had to be calculated and weightings applied. The weighting was calculated as
follows:
[8 ]

Weighted average of costs = Observed cost * Ni / N 2

Where:
Observed costs - cost of observed process ($/m^)
Ni = Trees affected by observed process
N 2 - Total trees in the treatment

This formula was used to calculate the weighted cost of manual felling, mechanized felling,
and hoe chucking. For total felling cost, the weighted manual and weighted mechanized
felling costs are combined.

25

In addition to direct harvesting production costs, landing and skid trails as well as moving
costs were calculated. Skid trail and landing construction costs were calculated from the
number of hours to construct the trail and landings and corresponding costs for each
treatment. The volume of timber removed from that treatment was then divided into the
corresponding costs using the same formula as planning and layout [1]. Moving costs of
equipment was also calculated for each treatment using equation 1. Average moving cost
was $600 per piece of equipment based upon a 35km round trip in the McBride area. This
was based on quotes from local contractors. Moving costs where the equipment was shared
for multiple treatments were weighted according to volume removed from each treatment
were calculated using equation 8 .

4.4.2.2 Standardization and Sensitivity Analysis
Tree volume has a large effect on the overall harvesting costs (Mann and Mifflin, 1979;
Kiuender et al., 1997). Skidding productivity is typically the most expensive component in a
whole tree harvesting operation and directly dependent on skidding distance (Mitchell,
2000). To understand better the influence of tree size and skidding distance on harvesting
cost, standardized values of tree size and skidding distance were used to compare costs for
planning and layout, skidding, processing, and loading between silvicultural treatments.

The standardization of merchantable volume per piece was calculated by substituting set
values for the merchantable volume per tree [Equation 5] and recalculating the hourly
production [Equation 6 ] and the final harvest cost [Equiation 7] for each harvesting process.

26

Skidding distance was standardized using the following methodology. A standard skidding
distance of 100 meters was entered into the derived general linear models (described in the
following section 4.4.3), while holding all other variables at their recorded average values, to
calculate the total productive eycle time.

Standardized values for merchantable volume per tree and skidding distance were used in the
derived general regression models (described in the following section 4.4.3), while holding
all other variables at their recorded average values. This allowed the calculation of the total
productive cycle time under the same condition of merchantable volume of tree size and
skidding distance. This productive cycle time was then used to calculate the cost per cubic
meter using the formulas [Equations 3-7] listed in section 4.2.2.1. After initial standardized
cost comparisons were completed, sensitivity analysis was conducted to see how these two
variables affect harvesting costs, while holding all other variables constant (Figures 6-10 and
12-13).

4.4.3

Objective 3 - Derive harvesting production prediction models based on appropriate
independent variables

For each harvesting component where detailed time studies were conducted, harvesting
prediction models were developed using the dependent and independent variables collected.
Both continuous and categorical independent variables were collected. All data analysis and
model creation was conducted using Systat 11 and Microsoft Excel 2003. The data collected
in the detailed time studies was entered into Systat 11 and checked form normality through
the creation of probability plots (Q-Q). The data was then taken into a Microsoft Excel

27

spreadsheet, where an initial screening of data was performed. Outliers were screened and
removed from the data set if they were more than 2 standard deviations from the mean. The
data was rechecked for normality post screening using Systat 11using a probability plot (QQ). A general linear model was then created using a stepwise process (a=0.05). When
independent variables were shown to be insignificant (P>0.05), they were removed and the
general linear model was rerun. A residual plots and lack of fit statistic were created for each
model revision. A straight line relationship of predicted values versus residual values in the
residual plot ensured that the data shows evidence that the distribution is normal in nature.
The significance of the independent variables was noted and a production model equation
created.

4.4.4

Objective 4 - Quantify residual stand damage fo r the different partial cutting
prescription blocks

Post harvest examination of retention patches and designated skid trails was conducted in
group retention and group selection treatment units. The block boundaries were also
examined in the clearcut and group retention treatments. Damage was quantified in three
main categories; root, stem, and crown damage. Root and stem scarring damage was
measured using a tape measure. The width, depth, and length of each scar or gouge were
recorded as well as its orientation and location on the tree and in the stand. Crown damage
was measured using a clinometer when the proportion of impacted live crown > 50% (Han
and Kellogg, 2000). Sampling was completed using a systematic line transect sampling
method. The intensity of the sample was determined by the following formula calculation of
the number of damaged trees needed for sampling (Thompson, 1992):

28

[9]
=

N *p ( U p )

-------

where:
no = number of damaged trees required in sample.
N
= total number of trees in the unit.
p
= estimate of % damaged trees in unit. The formula depends on the unknown
population proportion p. If no estimate of p is available before the survey a “worst
case” value of p = 0.5 can be used to determine sample size.
d
= width of the confidence interval, 5% in this study (d= 0.05).
z
= the upper a/2 point of the normal distribution (1.96 for 95% probability; a=0.05)

Once the number of damaged trees to be sampled was calculated, the sample area required
was derived. It was decided to apply the same sampling system at all sites to avoid sampling
error. Systematic transect sampling was initially chosen because there would be no damage
beyond one tree length from the boundary of openings and skid trails. It also provides
relatively consistent results and the low standard deviation (Han and Kellogg, 2000). The
systematic transects width was large enough to sample the residual-tree spacing but smaller
than the transect line spacing to avoid overlapping. Areas of harvested openings were not
considered part of the sampling area if traversed by a transect.

While sampling stand damage at the East Twin site, it was noted that all stand damage
occurred within 5 meters of a skid trail or opening. As a result, the sampling method was
changed to a systematic 25-meter wide strip along the edge of these features into the
remaining standing timber for the Minnow Creek site; East Twin site was resampled using
the 25-meter wide strip. Amount of damage present in the sample population was calculated
by dividing the number of sampled damaged trees by the sample population. Damage to the
residual stand was derived by dividing the number of sampled damaged trees by the number

29

of residual stems in the stand. Residual stems were ealculated by subtracting the number of
harvested trees in eaeh treatment from density information provided in the cruise data. An
assumption was made that no harvesting damage oceurred outside of the sample area and the
density information in the cruise data provided was eorrect.

30

5 Results and Discussions
The East Twin and Minnow sites will be reported and discussed as separate individual case
studies due to interaction of harvesting components and other variables such operator
experience and work habit differences. These inherent site differences do not allow for direct
comparison of the sites without first understanding each sites context.

5.1

East Twin

5.1.1

Planning and Layout

The planning and layout costs were highest, $2.62/m^, in the group selection because of the
need to designate removal patches in the block and a more complex skid trail system (Table
5). The most expensive cost components in planning/layout was traverse and boundary
marking, representing > 50% of total planning and layout cost. In all ground-basedtreatments, recommended skid trails were marked. In the group selection unit, the primary
goal of the layout crew was to design a skid trail system that would allow for multiple
entries. Pre-existing landings from earlier construction of the East Twin Forest Service Road
were utilized as an alternative to constructing new landings. The locations of these landings
were suitable and resulted in decreased landing construction costs. Layout cost per cubic
meter was lowest in the ground-based clearcut at $0.53/m^. The cable-based clearcut
incurred slightly higher costs ($ 0 .68 /m^) due to field survey requirements to ensure adequate
deflection for cable yarding throughout the block.

31

Table 5 Summary of East Twin planning and layout costs
Harvesting system
Silvicultural treatment
Traverse and boundary cost ($)
Deflection cost ($)
Mapping cost ($)
UNBC group selection layout cost ($)
Total cost ($)

Ground-based
Group selection
Clearcut
1095.00
232.75
n/a
n/a
78.75
12.55
750.00
n/a
1923.75
245.31

Cable
Clearcut
1248.41
730.00
67.34
n/a
2045.74

Final volume (m^)^^
2987.90
733.00
458.80
Layout / planning cost ($/m^)
262
0.53
0.68
®Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF

5.1.2

Harvesting Operations

5.1.2.1 Felling
Manual felling was the only method used partially or fully for all harvest units because of
large tree size (mean dbh was 53.2 cm) and steep slopes. When utilizing downhill felling and
top choking/hooking, breakage was a concern due to high decay levels, however breakage
occurred in < 2% of the felled and skidded timber. Contractor A and B had separate fellers
with similar amounts of felling experience (20 years). Felling production from the cable
clearcut is the highest at a cycle time of 1.97 minutes per tree (Table 6 ). This results in a
corresponding volume production of 358.08m^ felled timber per 8 -hour shift at a cost of
$1.12/m^ (Table 7). The second highest felling production occurred in the group selection.
The group selection cycle time was lower than that of the ground-based clearcut even though
precise directional felling was required. However, the higher volume per tree, 1.54m^/tree

for the ground-based portion of the clearcut versus 1.22 m^/ tree for the group selection
treatment, resulted in a larger volume harvested in the ground-based clearcut per cycle. As a
result the cost difference between the group selection and ground-based clearcut was only

32

$0.20/m^ A study in south east BC that had a tree size of 0.93m^/tree had similar manual
felling costs ranging from $2.1 i W to $2.28/m^ (Kockx and Krag, 1993). A more complete
summary of the felling cycle elements is located in Appendix 8 .

Table 6 Summary of East Twin felling cyele times
Harvesting system
Silvicultural treatment
Feller
Average time (min/cycle)
Total productive time
Total non-productive time
Total cycle time / tree
Average time (%/cycle)
Total productive time
Total non-productive time
Total cycle time

Ground-based
Group selection
A

Clearcut
A

Cable
Clearcut
B
1.29

1.27
3.13

T98
1.60
158

0.68

59.6
40.4

55.4
44.6

615
34.5

100.0

100.0

100.0

1.86

1.97

Table 7 East Twin felling productivity and cost
Harvesting system
Ground-based
Cable
Clearcut
Silvicultural treatment
Group selection
Clearcut
Feller
A
B
A
Net volume per tree (m^)“
L 22
1.54
1.47
Volume per hour (m^/hr)^
44.76
2137
2181
Labour and equipment cost (S/hr)*’
50.00
50.00
50.00
Felling cost (S/m^)’’
2.14
1.94
1.12
Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF
All costs and productivities are reported for scheduled machine hours.
The results from this study indicate that total cycle time, tree size, and decay percentage can
have an effect on the production. Designation of skid trails, tree species, feller, and treatment
type were significant factors relative to the delay-free cycle time (Table 8). Slope was found
to be not significant (P>0.05). Equation 10 describes the delay-free eycle time for manual
felling for all three East Twin treatments, determined from a general linear model analysis.

33

According to the general linear model, treatment type was a redundant variable as its
contribution was accounted for by the feller, road, and species variables; as such it was not
included in the model.

Table 8 Significance of East Twin independent felling variables to total productive
cycle time
Independent variables
81ope
8 kid trail designation
Feller
Tree species
Treatment

[10]

P value
0.479
0.004
0.001
0.000
0.001

Total productive cycle time (min) = 1.087 - 0.179F + 0.658Si - 0.33282 + 0.07278]
+0.292R

Where :
F = Feller (a=l, b=0)
8 1= Tree 8 pecies - western red cedar (if yes = 1, no = 0)
82 = Tree 8 pecies - western hemlock (if yes = 1, no - 0)
83 = Tree 8 pecies - subalpine fir (if yes = 1, no = 0)
R = Non-designated skid trails (if yes = 1, no = 0)

8 ample number = 656

R^ = 17.9%

8 tandard error of estimate = 1.01

In the cable unit, tree diameter data was collected. 81ope and tree species data was also
collected as independent variables, however it was found that only diameter was significant
(P<0.05) (Table 9). Equation 11 describes the delay-free cycle time for manual felling for a
cable-harvested unit, determined from a general linear model analysis. A significant linear
relationship was found between cycle time and diameter. Figure 1 illustrates the relationship
of productive felling cycle time to diameter.

34

Table 9 Significance of East Twin cable unit independent felling variables to total
productive cycle time
Independent variables
Slope
Diameter
Tree species

[11]

P value
0.670
0.000

0.452

Total productive cycle time for felling (min/cycle) = 0.040 + 0.020 * Diameter (cm)

Sample number =194

= 61.3%

Standard error of estimate = 0.469

3.5

20

40

60

80

100

120

140

Diameter at Cut (cm)

Figure 1 Relationship between total productive cycle time for felling and tree diameter
for the East Twin cable treatment

5.1.2.2

Primary Transportation

5.1.2.2.1 Skidding
Detailed skidding productivity for the John Deere 640 D line skidder is displayed in Table 10
and 11 for both treatments. A more complete summary of the skidding cycle elements is
reported in Appendix 9. The costs were $4.13/m^ to $4.47/m^ for the clearcut and group

35

selection treatments respectively. A study in a spruce dominant stand where the treatment
types were identical, 30% retention and clearcut, and the spread of average skidding
distances was 69 meters; the treatments had a skidding cost difference of $0.59/m^ (Sambo,
2003). The cost difference in this study was only $0.34/m^ while the skidding difference was
99 meters; however the clearcut unit had a greater proportion of non-productive time, causing
an increase in the cycle time.

The skidder in the ground-based clearcut employed 5 chokers, but 4 chokers were used in
most cases. In the group selection, the operator employed 8 chokers, using 6 of them in the
majority of instances. The operator felt the bladed trails would allow for more wood to be
hauled because of less obstruction from stumps and other remaining debris, and the longer
travel time required more volume to be delivered to the landing in order to be financially
viable. The average skidding distance in the group selection was 284 m, which was 143 m
longer than in the clearcut. As well, an additional 1.5 logs were delivered to the landing per
turn in the group selection each cycle resulting in longer cycle times. This resulted in a cycle
time that was 2.83 minutes greater in the group selection treatment.

Table 10 Summary of East Twin ground-based skidding cyele time
Harvesting system
Silvicultural treatment
Average time (min/cycle)
Total productive time
Total non-productive time
Total skidding cycle time
Average time (%/cycle)
Total productive time
Total non-productive time
Total cycle time

Ground-based
Group selection
Clearcut
18.47
2.87
21.34

15.50
3.01
18.51

86.55
13.45

83.74
16.26

100.00

100.00

36

Table 11 East Twin skidding productivity and cost
Harvesting system
Ground-based
Clearcut
Silvicultural treatment
Group selection
Average distance (m)
238.70
140.80
Average pieces/cycle (no.)
4.35
Net volume per tree (m^)‘*
1.22
1.54
Average volume/cycle (m^)
7.13
&69
Volume per hour (m^/hr)*’
21.72
20.09
Skidder cost (S/hry
89.74 .
89.74
Skidding cost ($/m^)’’
4.47
4.13
Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF
’’ All costs and productivities are reported for scheduled machine hours.
Figure 2 illustrates the proportion of eaeh delay that constitutes the non-productive time. In
the clearcut and group selection, 0 .6 % and 1. 1% of the total cycle time respectively was
spent waiting for the track skidder (Caterpillar D 6 ) to clear and develop skid trails. This
could have been avoided through better planning by the contractor. In the group selection
7.7% of the non-productive time is due to waiting for the feller. This occurred because trees
were felled into the same skid trail that the line skidders were using. In the clearcut, the skid
trail clearing time was higher than the group selection. This is the result o f having higher
stump heights and greater slash accumulation present than in designated skid trails. In the
group selection, chokers had to be replaced more often as the felled timber was often tangled
or caught on trees and stumps, and as a result greater stress was placed upon the choker
causing it to break.

37

M Personal

Mechanical

î 50 %

Z 40 %

Group selection

Clearcut

km

Group selection

@ Operational

Clearcut

Figure 2 Summary of East Twin non-productive timing elements for skidding

Through a general linear model analysis, the following factors significantly influenced the
delay-free total productive time: number of log skidded per turn, and skidding distance
(Table 12). Average slope, treatment, skid trail designation, and number o f chokers available
were not significant factors (P>0.05).

38

Table 12 Significance of East Twin independent skidding variables to total productive
cycle time
Independent variables

P value
(1789
(1299
0.085

Slope
Skid trail designation
Treatment
Logs skidded
Chokers present
Skidding distance

0.001

fr278
0.000

Equation 12 describes the total productive cyele time (delay-free) for a rubber-tired line
skidder, determined from a general linear model analysis.
[12]

Total productive time (min) = 8.321 + 0.023 * Distance + 0.745 * No of logs

Sample number =139

= 0.512

Standard error of estimate = 3.243

5.1.2.2.2 Yarding
A Madill JVC tower yarder used a running skyline system with a non-slackpulling carriage,
with 5 chokers attached to it. The yarding was downhill with distances ranging from 35 to
225 meters with an average distance of 156 meters. Cycle time data for this yarder is
displayed in Table 13 and Appendix 10. The unit cost for yarding was $7.74/ m^, which is
73.2% more expensive than skidding in the group selection and 87.2% higher than skidding
in the ground-based clearcut (Table 11 and 14). While the production was similar to other
skyline studies, 32.49m^/PMH versus 25.7m^/PMH to 37.9m^/PMH (Hedin and Delong,
1993), the yarding costs were considered low in comparison to the costs reported from other
studies in cedar dominant stands in the province. This might be the result of the wages of the
crew ranging from $20 to $25 per hour plus benefits where wages elsewhere in the province
are on average $ 10/hr higher plus benefits. The productive yarding time constitutes 75.1% of
the total cycle time. This is higher than that found in the study by Pavel near Kitwanga, BC

39

(1999), which found that only 55% of the total cycle time was actually productive. Yarder
setting change time accounts for 11% of the total cycle time, this is between two FERIC
skyline analyses that were 10% (Dunham and Gillies, 2000) and 15% of the total cycle time
(Kosicki, 2000b).

Table 13 Summary of East Twin yarding cycle time
Total productive time
Total non-productive time
Total cycle time

Average time (min/cycle)
7.08
2.34
9.42

Average time (%/cycle)
75.10
24.90
100.00

Table 14 East Twin yarding productivity and cost
Cable
Clearcut
Pieces per cycle (no.)
259
1.47
Net volume per tree (m^)®
Volume per cycle (m^)
3.81
Average yarding distance (m)
155.98
Timed cycles (no.)
297
Volume per hour (m^/hr)'’
2425
Yarder cost ($/hr)*’
187.58
7.74
Yarding cost ($/m^)"^
^Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF
’’ All costs and productivities are reported for scheduled machine hours.
Harvesting system
Silvicultural treatment

The hook up time was the most time consuming component, 46% of the total cycle time,
followed by the inhaul element (Figure 3, Appendix 5). The hook up time was the most
physically demanding portion of the yarding cycle. In order to hook up timber, the hook
tenders on the hill must pull the chokers attached to the 250-kilogram non-slack pulling
carriage toward the felled tree, often not only pulling the weight of the carriage and choker
but also a portion of the yarding lines, mainline and haul back. There were five chokers
attached to the carriage. Therefore during the hooking process, the hook tenders attempted to

40

hook up to 5 trees, by repeating the hooking process. In most cases only 2 chokers were
utilized due to large tree size and the scattered distribution of felled trees. The felled logs
were top choked as it was faster than butt choking due to decreased tree diameters.

31.7%
QOuthaul

□ Hookup

11 . 8 %

46.0%

B Inhaul

I Unhook

10.4%

Figure 3 Productive cycle time distribution for East Twin cable yarding

Approximately 8.1% of the non-productive time, or 2.1% of the total cycle time, was spent
on repairing the haulback drum and general repairs, such as repairing a coolant leak or
broken hydraulic line. A skyline study by Dunham and Gillies (2000) found the repair time
to be lower at 2.0% of the total cycle time. The time to replace chokers accounted for 7.8%
of the non-productive time.

41

32.3%

0 Operational

□ Mechanical

0 .8%

66.9%

■ Personal

Figure 4 Non-productive cycle time distribution for East Twin cable yarding
Through a linear regression analysis, the delay-free total productive time, the number of logs
yarded and yarding distance were found to be significant factors (Table 15). As the number
of chokers available did not change throughout the study it was not considered. Average
slope was found to be an insignificant factor.

Tabic 15 Significance of East Twin independent yarding variables to total productive
cycle time
P value
0.487

Independent variables
Slope
Logs yarded
Yarding distance

0.000
0.000

Equation 13 describes the total productive cycle time (delay-free) for a single span, running
skyline system, determined from a general linear model analysis.
[13]

Total productive time (min) = 2.002 + 0.027 * Distance (m) + 0.639 * No. of logs

Sample number = 285

= 29.0%

Standard error of estimate = 1.791

42

5.1.2.3 Manual processing
Processing for all sites was completed manually at the landing. The primary consideration of
processing was to maximize commercially valuable wood recovery such as saw logs and post
and rail wood. The site with the lowest cost was the ground-based clearcut; again this may
be due to the lowest defect rate per tree and the higher proportion of spruce and subalpine fir
(Table 16 and 17). The combined felling and processing costs were $2.27/m^ to $3.68/m^. A
study in the ICH mc2 had combined costs of $3.23W (Kosicki, 2000a).

Table 16 East Twin shift level summary for manual processing
Harvesting system
Ground-based
Cable
Group selection
Clearcut
Silvicultural treatment
Clearcut
B
Bucker
A
A
18.75
138.00
Time (hrs)
45.25
Trees processed (no.)
601
298
2033
2.14
2.14
Gross volume per tree (m^)®
2.66
1.54
Net volume per tree (m^)’’
1.22
1.47
1.02
1.15
1.54
Cost ($/m^)®
“ Provided by the BC MOF Cruise report.
Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF
" All costs and productivities are reported for scheduled machine hours.

Table 17 East Twin species volumes for eaeh treatment^
Ground-based
Silvicultural treatment
Group selection
Clearcut
Volume (m^)“
Cedar
382.1 (78.7)
673 (91^0
Spruce and subalpine fir
60(8.2)
103.7 (21.3)
Hemlock
Total
733 (100.0)
485.8(100.0)
Values in ( ) indicate % of the total volume.
' Net merchantable volume was provided by the BC MOF

Cable
Clearcut
2793.6 (93.5)
76.5 (2.6)
117.8(3.9)
2987.9 (100.0)

43

The saw logs were required to have a 10cm shell (distance between outer bark and inner rot)
of timber in order to be merchantable. The minimum required length for saw logs was 5m to
a maximum length of 19m. These saw logs will be processed into small dimension aesthetic
lumber. The post and rail timber required a 7.5cm shell. Post and rail timber required a
minimum length of 2.5m and a maximum length of 19m. Bucker “A” was used in both
ground-based treatments, while a different bucker was used in the cable clearcut, bucker “B”.
Bucker “B” was the owner of the cable operation. He felt that by processing the wood
himself, he could achieve the maximum commercial value from the timber.

The combined decay, waste, and breakage estimates from the BC MOF cruise data for the
ground-based group selection, ground-based clearcut, and cable clearcut treatments were
68 %, 51%, and 52%, respectively. Observations support these numbers as a large incidence

of butt and pocket rot in cedar logs was present. Butt and pocket rot not only destroy
heartwood and sapwood, but also increases the possibility of breakage when felling and
skidding/yarding. Increased breakage however was not observed during felling or skidding.
The decay level required the bucker to make multiple cuts at 0.75m intervals to determine
where the timber was commercially valuable. In the cable clearcut, the timber was first
processed for saw logs and then post and rail wood. The hemlock, spruce, and subalpine fir
had little decay, thus was faster to process for the bucker. These species were processed for
saw logs only.

In the cable block, it was observed that the bucker “B” was able to retrieve more commercial
volume than bucker “A” from cedar, by processing the wood for both saw logs and post and

44

rail timber. In the group selection and ground-based clearcut, the cedar was only processed
for saw logs due to inexperience of Contractor “A” in processing defective cedar. This is
illustrated in the final volume scale data; as the final volumes per tree of both clearcut
treatments are very similar while the proportion per species varies (Table 17).

5.1.2.4 Decking
Loading was not completed after harvesting due to road restrictions. Therefore, the timber
was not loaded onto trucks during harvesting, but instead decked on the landing. As a result,
the loading cost is equivalent to the decking cost. Loading costs were the highest in the
group selection at $5.32/m^ because less skidded volume was available for the loader as a
result of longer skidding cycle times (Table 18). The ground-based and cable clearcut cost is
$3.33/m^ and $5.01/m^, respectively. The cable clearcut had higher costs than the groundbased clearcut largely due to higher equipment costs per hour, although a heel-boom loader
showed a greater productivity (m^/hr) than the front-end loader in the group selection. The
contractor chose a heel-boom loader, as it requires less operating space on the landing than a
front-end loader. In this yarding operation, landing area was minimal being only 45 by 45
meters. These costs are between values reported in previous studies such as $6.81/m^
(Pavel, 1999), $2.32/m^ (Pavel 2004), and $3.52/m^to $9.94/m^ (Pavel, 2005).

45

Table 18 East Twin shift level summary for loading
Harvesting system
Ground-based
Cable
Silvicultural treatment
Group selection________Clearcut___________ Clearcut_____
Equipment
Front-end log loader Front-end log loader Heel-boom loader
Net volume per tree (m^)‘‘
1.22
1.54
1.47
Volume processed (m^/hr)*’
16.20
25.91
21.65
Equipment rate ($/hr)'’
86.16
86.16
108.51
Cost ($W )^____________________ 5 J2 ______________ 333______________ 531_______
^Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF
*’ All costs and productivities are reported for scheduled machine hours
5.1.2.5 Other Harvesting Costs
Equipment moving cost and skid trail and landing construction costs should be considered as
part of the final cost. The summary of moving costs was based on moving equipment from
McBride to the harvest site, a 35km distance (Table 19).

Table 19 Summary of East Twin equipment moving costs
Ground-based
Harvesting system
Group selection
Clearcut
Silvicultural treatment
Move in and out cost ($)
721.69
478.31
Final net volume (m^)'^
733.00
485.80
Cost ($ W )
0.98
0.98
" Net merchantable volume was provided by the BC MOF

Cable
Clearcut
1200.00

2987.90
0.40

The group selection required 15 hours of landing and skid trail construction to harvest a
lower proportion of wood than the ground-based and cable clearcut, where only 7.5 hours
was spent for landing and skid trail construction (Table 20). This resulted in a higher cost
per cubic meter in the group selection. The cable and ground-based clearcut utilized the
same landing and no skid trails were constructed, thus the construction costs were shared by
a volume basis. As landings were pre-existing, and only required slight modifications to

46

bring them up to legislative requirements, these results will not be included in the
comparison of harvesting costs between treatments.

Table 20 Summary of East Twin skid trail and landing construction costs
Ground-based
Harvesting system
Silvicultural treatment
Group selection
Clearcut
Time (hrs)
15.00
1.05
Equipment and manpower ($/hr)®
145.09
145.09
Final net volume (m^)'’
485.80
733.00
Cost ($/m^)"
0.31
2.97
' All costs and productivities are reported for scheduled machine hours.
’’ Net merchantable volume was provided by the BC MOF

5.1.3

Cable
Clearcut
6.45
145.09
2987.90
0.31

Summary o f Harvesting Costs

The unit cost ($/m^) was lowest in the ground-based clearcut treatment (Table 21). The
ground-based clearcut had the lowest costs because of minimal planning and layout
requirements, and a higher volume of merchantable timber extracted per tree. The planning
and layout costs were highest, $2.62/m^, in the group selection because of the need to
designate removal patches in the block. The cable-based clearcut incurred slightly higher
costs ($0.68/m^) than the ground-based clearcut due to increased time requirements for
skyline corridor layout. The increased volume was the result of more non-cedar species with
fewer defects than cedar. The low defect level allowed the bucker to process the logs
without making multiple cuts, thus increasing productivity. The cable clearcut treatment had
the second lowest unit cost as the result of lower felling and moving costs due to shorter total
felling cycle time and greater total volume being removed from the treatment, respectively.
The group selection had the highest cost as a result of having the lowest merchantable
volume per tree and long skidding distance. The skidding distance in the group selection was
nearly twice that of the ground-based clearcut. As a result of increased skidding distance, the

47

skidding cycle time increased by 2.83 minutes. This resulted in the bucker and loader
waiting for wood to process.

Table 21 Summary of East Twin total costs ($/m^)*
Ground-based
Group selection
Clearcut
0.53
2.62
2.14
1.94
4.13
4.47
1.54
1.02
5.32
3.33

Cable
Clearcut
0.68
1.12
7.74
1.15
5.01

10.95
16.09
Total cost
"I"';.,"'"'"
.
.
..
...
All costs and productivities are reported for scheduled machine hours.

15.70

Harvesting system
Silvicultural treatment
Layout/planning cost
Felling cost
Skidding/yarding cost
Processing cost
Loading cost

The results and discussion presented here were based upon relatively small treatment units
ranging in size from 1.1 ha to 5.8 ha. Aecording to the final volume data, the volume per ha
is greater in the ground-based clearcut treatment than in the other treatments due to a slightly
lower defect percentage, 51% versus 52% in the cable clearcut and 68% in the group
selection treatment. This defect variation results in a merchantable volume difference of
8.6m^/ha in the cable elearcut and 92.6m^/ha in the group selection compared to the groundbased clearcut. As a result of this higher volume, the ground-based cleareut has lower
planning and layout, manual processing, skidding, and loading costs than the group selection
or cable cleareut.

If the merchantable volume per tree was identical (Im^/tree) in each treatment and the
number of harvested trees in each treatment remained constant, the group selection
harvesting system would cost $19.63/m^ due to a decrease in merchantable volume per piece
(Table 21). This is an increase of $3.54/m^. The clearcut cable costs would also increase by

48

$7.3 8/m^ to $23.08/m^ because of decrease in piece size. The cost of the clearcut unit would
increase by $5.91/m^ due to a decrease in average piece size of 0.54m^.

Table 22 Summary of East Twin total costs ($/m^) at a standardized merchantable
volume per stem of Im^ ^
Harvesting system
Silvicultural treatment
Layout/planning cost
Felling cost
Skidding/yarding cost
Processing cost
Loading cost

Ground-based
Group selection
Clearcut
0.82
3.20
2.61
2.98
5.45
6.36
1.88
1.57
5.12
6.49

Cable
Clearcut
1.01
1.64
11.37
1.70
7.37

16.86
Total cost
19.63
... reported for scheduled machine hours.
All costs and productivities-are

23.08

T " . ---------........... ..

5.1.4

Landing Activity

According to the activity sampling, primary transportation was not delayed by loading and
manual processing on the landing (Table 23). In the ground-based treatments, the loader and
the bucker were idle and waiting for processing of timber for 54% and 47 % of the scheduled
operating time, respectively. To improve loading and manual processing efficiency on the
landing in the ground-based treatments, another skidder may be employed to reduce the non­
productive time. However, this may result in skidding delays unless an appropriate work
plan is prepared. In the cable treatment, the operation was well balanced in its components.
A more detailed summary is provided in Appendix 11.

49

Table 23 Summary of East Twin landing activity sampling
Harvesting system
Ground-based
Cable
Silvicultural treatment_______Group selection_____ Clearcut_________Clearcut
Time (min)
Delayed
0.00
0.00
0.00
Skidder/yarder
60.000
Productive
60.00
60.00
32.14
Delayed
32.67
14.25
Loader
Productive
45.75
27.86
27.33
17.25
Delayed
31.53
32.00
Bucker
Productive
28.47
42.75
28.00

Skidder/yarder
Loader
Bucker

5.1.5

Delayed
Productive
Delayed
Productive
Delayed
Productive

0
100
54
46
53
47

Time (%)
0
100
54
46
53
47

0
100
24
76
29
71

Stand Damage

In the group selection treatment, the residual stand damage was classified by the type of
damage and location relation to harvesting infrastructure (Table 24). Seventy seven percent
of the total damage was located within 5 meters from the centre of a skid trail while the
remaining 23% was located within 5 meters of harvest block boundaries. Using criteria in
Pavel (1999), 51 trees along the skid trail, 3 trees in the patch opening and 6 trees at the
junction of the openings and skid trails, showed damage considered unacceptable for
retention as residual crop tree in the group selection treatment. Only 1 tree along the
boundary of the cable portion of the clearcut was considered unacceptable.

50

Table 24 Stand damage summary for East Twin group selection treatment
Harvesting system
Silvicultural treatment
Feature
Damage summary
No. of sampled trees
No. of injured trees
% of sampled trees®
% of residual stand*’
No. injuries/tree
Average size
Width (cm)
Length (cm)
Area (cm^)
Height (cm)“

Ground-based
Group selection
Openings
Junctions
Skid trails

Clearcut
Boundary

Cable
Clearcut
Boundary

425
69
16.2
2.0
1.2

796
13
1.6
0.4
1.1

83
8
9.6
0.2
1.6

92
2
2.2
n/a
2.0

605
2
0.3
n/a
1.5

17.1
45.8
783.2
135.6

13.1
30.1
393.1
82.0

20.1
42.2
846.3
81.2

14.0
23.0
322.0
37.3

12.0
42.0
504.0
125.0

Percent of total damage'*
Stem
100.0
100.0
100.0
100.0
86.5
Stem and root
0.0
0.0
0.0
12.1
0.0
Root
0.7
0.0
0.0
0.0
0.0
Crown
0.7
0.0
0.0
0.0
0.0
Sampled trees = sample population
’’ Residual trees = total population - calculated from cruise and harvesting data
" Measured from base of tree to middle of damage
Damage classes: Stem - Stem damage only. Stem and root - Stem and root damage combined,
Root - Root damage only, and Crown - All crown damage.

51

5.2

Minnow Creek

5.2.1 Planning and Layout
The planning and layout costs were highest, $1.73/m^, in the group selection because of the
need to designate removal patches and larger block perimeter (Table 25). The costs were
also 1.6 times higher in the group retention than the clearcut due to the need to designate
retention patches and a greater block perimeter. As result of not having to designate removal
or retention patches, the layout cost was lowest in the ground-based clearcut at $0.45/m^.

Table 25 Summary of Minnow planning and layout costs
Silvicultural treatment
Group selection Group retention
Traverse and boundary cost ($)
1377.60
1281.77
Mapping and office cost ($)
157.40
146.45
UNBC group selection layout cost ($)
750.00
750.00
Total cost ($)
2178.22
2285.00
Final volume (m^)®
1323.26
1883.62
Layout / planning cost ($ W )
1.73
1.16
Net merchantable volume was provided by the BC MOF

Clearcut
1078.13
123.18
n/a
1201.31
2657.78
0.45

Pre-existing skid trails and a landing from previous harvest units were used when possible.
This resulted in decreased landing and skid trail construction costs. During harvesting the
closest landing was utilized, often resulting in the same landing being utilized for multiple
treatments.
During manual felling, it became clear that marking with colours such as red and greens
should be avoided due to colour blindness concerns. The manual feller observed reds as a
brown colour, making the marks hard to distinguish from the bark. Upon further research, it
was found that roughly 10% of the male population is color blind (Neitz et al, 1989).

52

5.2.2

Harvesting Operations

5.2.2.1 Felling
Even though mechanical felling, using a Timberjack 618 feller buncher, in the clearcut had
the fastest cycle time of 1.35 minutes per tree, production was highest in the group retention
treatment due to the greatest merchantable volume per tree (Table 26 and 27; Appendix 12).
The second highest production occurred in the group selection, again due to a higher
merchantable volume per tree. The clearcut felling cycle time was the shortest but due to the
lowest average merchantable volume per tree, the observed mechanical felling cost was
$3.60W . Felling costs were similar to two FERIC studies in the interior of BC due to
similar production $3.44m^ to $3.77m^ (Gillies, 2002) and $2.71m^ to $3.39m^ (Sambo,
2003). If the volume per tree was standardized for all treatments, Im^ per tree, the observed
cost would have been lowest in the clearcut, followed by the group retention, and lastly by
the group selection at $3.29/m^, $3.45/m^, and $3.60W , respectively. This indicates that
tree size, and decay percentage can have an effect on felling production cost. During felling,
snow was present on the site and repeatedly caused the buncher to slide downhill. In the case
of manual felling, the snow had no observable effect on productivity. As manual felling was
utilized top fell a proportion of each unit, weighted mechanized and manual felling costs
were calculated to determine the contribution of the each felling method to the total felling
cost.

53

Table 26 Cycle time of Minnow mechanized felling phase
Silvicultural treatment
Average time (min/cycle)
Total productive time
Total non-productive time
Total cycle time
Average time (%/cycle)
Total productive time
Total non-productive time
Total cycle time

Group selection

Group retention

Clearcut

0.82
0.59
1.41

0.87
0.48
1.35

0.87
0.42
1.29

57.99
42.01
100.00

64.27
35.73
100.00

67.54
32.46
100.00

Table 27 Summary of Minnow mechanized felling costs
Silvicultural treatment
Average slope (%)
Percent of total trees multicut (%)
Net volume per tree (m^)^
Volume / hour (m^/hr)*’
Equipment and labour rate (S/hr)’’
Observed felling cost (S/m^)’’

Group selection Group retention
21.04
12.17
3.24
16.81
1.05
1.07
44.85
47.79
153.24
153.24
3.42
3.21

Clearcut
28.49
10.14
0.91
42.52
153.24
3.60

Weighted average felling cost (S/m^)’’
3.22
2.96
3.15
“Net merchantable volume per tree was caleulated from the provided merchantable volumes from the
BCMOF
^ All costs and productivities are reported for scheduled machine hours
Equation 14 describes the total productive cycle time (delay-free) for a feller buncher,
determined from a general linear model analysis. Slope and the use of multiple cuts to fell a
tree were significant factors (P<0.05), while treatment and tree species were insignificant
factors (Table 28).

Table 28 Significance of Minnow independent felling variables to total productive cycle
time
Independent variables
Slope
Tree species
Skid trail designation
Treatment
Multiple cuts

P value
0.000
0.964
0.457
0.664
0.000

54

[14]

Total productive cycle time (min) = 1.391 + 0. 006S - 0.785M q - 0.1 lOMi

Where :
S = slope (%)
Mo = No multiple cuts required (if yes = 1, no = 0)
Ml = One multiple cut required (if yes = 1, no = 0)
Sample number =1153

= 20.3%

Standard error of estimate = 0.542

A total of 507 trees were manually felled in the study with the majority being in the clearcut
treatment (Table 29). The highest felling cost was observed in the group retention due to the
spread-out locations of the trees to be felled. When this cost was weighted for its felling
contribution, the overall manual felling cost was lowest in the group retention. The trees in
the group retention were manual felled due to tree characteristics where in the group
selection and clearcut treatments, tree were being manually felled as a result of both tree
characteristics and steep slopes. It should be noted that the feller employed was colour blind
and had problems seeing reds, the colour used to mark trees for removal in the group
selection treatment. In the future, such marking should be colour blind friendly, reds and
greens should be avoided.

Table 29 Summary of Minnow manual felling costs
Silvicultural treatment
Time (hrs)
Trees felled (No)
Net volume per tree (m^)^
Feller cost ($/hr)
Observed felling cost ($/m^)'^

Group selection Group retention
10.25
2.50
34
168
1.05
1.07
50.00
50.00
2.90
3.43

Clearcut
14.00
305
0.91
50.00
2.52

0.07
Weighted average felling cost ($/m^)*’
0.39
0.26
" Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF
**All costs and productivities are reported for scheduled machine hours

55

5222

Skidding

Ground-based skidding techniques were used for all treatment units. Cycle time data for the
John Deere 748E grapple skidder is displayed in Table 30 for all three treatments. A more
complete summary of the skidding cycle elements is given in Appendix 13. As mentioned,
both feller bunching and hoe chucking were utilized to group logs for greater grapple skidder
efficiency.

Table 30 Cycle time of Minnow ground-based skidding phase
Silvicultural treatment
Average time (min/cyele)
Total productive time
Total non-productive time
Total cycle time
Average time (%/cycle)
Total productive time
Total non-productive time
Total cycle time

Group selection

Group retention

Clearcut

8.63
4.51
13.14

7.27
1.72
8.99

11.07
3.39
14.47

65.67
34.33
100.00

80.89
19.11
100.00

76.56
23.44
100.00

The highest productivity was observed in the group retention treatment due to gentle slopes
and a shorter average skidding distance equivalent to half of the average skidding distances
in the group selection and clearcut treatments (Table 31). While a greater number of logs per
cycle were delivered to the landing in the clearcut, a lower average volume per log and
greater cycle time still resulted in it having the lowest productivity and highest costs. Studies
by Hedin and DeLong (1993) and Kellogg et al (1991) also found that m3/log and number of
logs/turn had a significant impact on harvesting cost.

56

Table 31 Summary of Minnow skidding production and costs
Silvicultural treatment
Average pieces/cycle (no.)
Average slope (%)
Average turn length (m)
Average distance loaded (m)
Average distance empty (m)
Tums hoe chucked (%)

Group selection
4.83
15.5
26.2
246.8
246.8
20.18

Group retention
4.60
13.4
28.3
133.9
133.9
0

Clearcut
5.63
27.2
25.0
273.7
289.3
25.58

Net volume per tree (m^)®
1.05
1.07
0.91
Volume / tum (m V
4.94
5.09
5.13
Volume / hour (m /hr)'’
21.29
23.25
32.95
116.26
Equipment and labour rate ($/hr)
116.26
116.26
Skidding cost ($/m^)'’
5.00
5.46
3.53
“Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BC MOF
*’ All costs and productivities are reported for scheduled machine hours

Figure 5 illustrates the proportion each delay that constitutes the non-productive time. The
group selection had the greatest amount of non-productive time per cycle at 4.51 min/tum
followed by the clearcut and group retention at 3.39 min/tum and 1.72 min/tum, respectively.
The largest delay observed in all three treatments occurred in the group selection and was
due to a sheared blade pin on the skidder. This delay accounted for 11.9% of the total cycle
time, and if it had not occurred, skidding in the group selection would have had a cost of
$4.41/m^, reducing the cost by $0.59/m^.

57

100 %

90%

80%
I P erso n al

70%

?i

60%

•a

o

50%
I M echanical

40%

30%

20%

I

10%

B O p e ra tio n a l

I
G roup se le c t io n

G roup rete ntion

C le a rc u t

Figure 5 Summary of Minnow non-productive timing elements for skidding

Through a general linear model analysis, the delay-free total productive time was
significantly affected by the following factors: average skidding distance, number of logs per
tum, maximum length of logs skidded, slope, and treatment (Table 32). The use of hoe
chucking or skid trail designation did not have a significant effect.

58

Table 32 Significance of Minnow independent skidding variables to total productive
cycle time
Independent variables
Distance
Logs skidded
Maximum length of skidded logs
Skid trail designation
Slope
Treatment
Hoe chucked wood

P value
0.000
0.000
0.000
0.866
0.001
0.000
0.289

Equation 15 describes the total productive cycle time (delay-free) for a grapple skidder,
determined from a general linear model analysis. A significant linear relationship was found
between total productive time, treatment, distance, slope, maximum length of logs in a tum,
and number of logs per tum.
[15]

Total productive cycle time (min) - 0.278 + 0. 017D + 0.316Lg + O.lOBLn + 0.027S 0.647GS - 0.086Gr

Where :
D = Distance skidded (m)
Lg = Number of logs
Ln = Maximum length logs in a tum (m)
S = Slope (%)
Gs = Group selection treatment (if yes - 1, no = 0)
Gr = Group retention treatment (if yes = 1, no = 0)
Sample number = 1066

= 62.9%

Standard error of estimate = 2.60

5.2.2.3 Hoe Chucking
Hoe chucking was only required in the group selection and clearcut treatments and had an
observed cost of $6.34/m^ and $4.67/m^, respectively. When these costs are weighted by
contribution, these costs were $ 1.02/m^ for the group selection and $1.17/m^ for the clearcut
treatment.

59

Table 33 Minnow shift level summary for hoe chucking
Silvicultural treatment
Time (hrs)
Equipment and labour rate ($/hr)^
Trees hoe chucked
Net volume per tree (m^)®
Volume hoe chucked (m^)
Observed hoe chucking cost ($/m^)*’

Group selection Group retention
13
0
103.48
103.48
202
0
1.05
1.07
0.00
212.10
0.00
6.34

Clearcut
30
103.48
730
0.91
664.30
4.67

Weighted average hoe chucking cost
1.02
0.00
1.17
($/m^)"
“Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF
All costs and productivities are reported for scheduled machine hours
5.2.2.4 Processing
Processing for all treatments was completed manually. The primary consideration of
processing was to maximize commercially valuable wood recovery. The priorities were as
follows: peelers, saw logs, post and rail wood, and finally pulpwood. The minimum
requirements of a peeler are as follows: >75% sound wood of either spruce or subalpine fir,
with the sound wood being > 20.3cm (8in) in diameter, a minimum length of 5.3m (17ft 4in)
to 15.8m (51ft 9in) in length. In order to be suitable for a saw log, 50% of the wood has to
be sound with the sound wood being a minimum of 10cm (4in) of sound wood. All species
except hemlock on site were suitable for the production of saw logs as the trucking costs of
hemlock to the nearest processing facilities were prohibitive. The minimum required length
for saw logs was 3.7m (12ft) to a maximum length of 15.8m (51ft 9in). In the case of cedar,
these logs will be processed into small dimension aesthetic lumber. Cedar was also
processed into post and rail timber which required a minimum 7.5cm (3in) shell of clear solid
wood and length of 2.5m (8ft 3in) to 15.8m (51ft 9in). The combined decay, waste, and
breakage estimates for the group selection, group retention, and clearcut treatments were

60

55%, 53%, and 68%, respectively. Identical processing techniques were used in Minnow as
East Twin.

The treatment with the lowest processing cost was the group retention followed by the group
selection and clearcut. This might be the result of the group retention having the lowest
decay waste and breakage rates and the higher proportion of spruce and subalpine fir (Table
34 and 35). The hemlock, spruce, and subalpine fir on site had less decay, thus was faster to
process.

Table 34 Minnow shift level summary for manual processing
Silvicultural treatment_______ Group selection Group retention_____ Clearcut
57
128
Time (hrs)
79
Trees processed (no.)
1256
1756
2916
Gross volume per tree (m ^f
2.35
2.29
2.85
Net. Volume per tree (m^)
1.05
1.07
0.91
Cost ($W)=
1.08
1.05
1.21
^ Provided by the BC MOF Cruise report.
^ Net merchantable volume per tree was calculated from the provided merchantable volumes from the
BCMOF
° All costs and productivities are reported for scheduled machine hours.

Table 35 Minnow species volumes for each treatment^
Silvicultural treatment
Volume (m^)®
Cedar-saw logs
Cedar - post & rail

Group selection

Group retention

Clearcut

369.6(27.9)
405.8 (30.7)

457.5(24.3)
385.0 (20.4)

925.9(34.8)
646.0 (24.3)

1019.3 (54.1)

1073.4 (40.4)

21.8(1.2)
1883.6(100.0)

12.4(0.5)
2657.8(100.0)

Spruce and subalpine fir
515.8 (39.0)
- dry logs, saw logs, and peelers
H em lock-pulp
32.0(2.4)
Total_________________________ 1323.3 (100.0)
*Values in ( ) indicate % of the total volume.
“Net merchantable volume was provided by the BC MOF

61

Several improvements can be made in the felling o f trees that can improve the efficiency of
the bucker. These include manual felling larger trees regardless of species to minimize butt
shatter and stump pull and when using multiple cuts during mechanical felling, cuts should
be matched to ensure a level flat cut on the bottom log.

5.2.2.S Loading
The timber on this site was sorted into six product categories: dry spruce, spruce and
subalpine fir peelers, spruce and subalpine fir saw logs, cedar saw logs, cedar post and rail
timber, and hemlock pulp. As a result of these multiple sorts, landing space became an issue
on landing 2 as it was the smallest of the three landings measuring 50 m by 50 m while
landing 1, a pre-existing landing, measured 150 m by 50 m, and landing 3 measured 80 m by
40 m. This effect can be observed in the loading costs below as the group selection treatment
primarily used landing 2 and had the highest loading cost at $4.75/m^ compared to the group
retention and clearcut which had costs of $4.44/m^ and $4.18/m^ respectively (Table 36). In
the group selection treatment, the loading cost was increased by a greater amount of
unproductive time due to delays and lack of wood to process (Table 41).

Table 36 Minnow shift level summary for loading
Silvicultural treatment
Volume per tree (m"*)^
Volume processed (m^/hr)'’
Equipment and labour rate ($/hr)^
Cost ($W )"

Group selection
1.07
19.36
91.97
4.75

Group retention
1.05
20.7
91.97
4.44

Clearcut
0.91
22.03
91.97
4.18

^ N e t m e rc h a n ta b le v o lu m e p e r tre e w a s c a lc u la te d fro m th e p ro v id e d m e rc h a n ta b le v o lu m e s fro m th e

BC MOF
All costs and productivities are reported for scheduled machine hours

62

5.2.2.6 Other Harvesting Costs
Equipment moving cost and skid trail and landing construction costs should be considered as
part of the final cost (Table 37 and 38). The group retention treatment required 24 hours of
landing and skid trail construction, compared to 55 and 71 hours for the group retention and
clearcut units due to minimal upgrade in the existing harvesting infrastructure to bring it up
to legislative standards. This was also true for over half of the skid trails required in the
group selection; however a landing had to be constructed so that skidding costs would be
reduced. The clearcut required both the construction of skid trails and a landing, and as a
result had the greatest amount of hours spent in constructing these features. As the costs are
dependent on the volume of timber removed, the costs are lower in the clearcut versus the
group selection as more volume was removed from the same amount of area. The group
retention had the lowest costs as the features were already pre-existing. As skid trails and
landings were pre-existing in some of the treatments, these results will not be included in the
comparison o f harvesting costs between treatments.

Table 37 Summary of Minnow Twin equipment moving costs
Group selection
Silvicultural treatment
676.90
Move in and out cost ($)
Final net volume (m^)®
1323.26
Cost ($/m^)
0.51
' Net merchantable volume was provided by the BC MOF

Group retention
963.54
1883.62
0.51

Clearcut
1359.56
2657.78
0.51

63

Table 38 Summary of Minnow skid trail and landing construction costs
Silvicultural treatment_______ Group selection
Time - excavator (hrs)“
31.00
Excavator and labour cost (S/hr)®
103.48
Time - bulldozer (hrs)®
24.00
Bulldozer and labour cost ($/hr)®
111.78
5890.51
Total costs ($)®

Group retention_____ Clearcut
9.00
38.50
103.48
103.48
15.00
32.50
111.78
111.78
2608.01
7616.73

Final volume (m^)'’
1883.62
1323.26
Cost ($/m^)®
4.45
1.38
" All costs and productivities are reported for scheduled machine hours.
’Net merchantable volume was provided by the BC MOF
5.2.3

2657.78
2.87

Summary o f Harvesting Costs

The unit cost ($/m^) was lowest in the group retention treatment, $13.45/m^, as a result of
having the shortest average skidding distance, gentle slope, no hoe chucking, less manual
felling, and a higher volume of merchantable timber extracted per tree. The increased
volume is the result of more non-cedar species being present. These species have a lower
level of defect than cedar on this site and this lower defect level allowed the bucker to
process the logs without making multiple cuts, thus increasing productivity and efficiency.
The clearcut had the second highest cost at $16.3SW due to a longer skidding distance,
steeper slopes, and lower merchantable volume per extracted tree than in the group retention.

Table 39 Summary of Minnow total costs ($/m3\1
)
Silvicultural treatment
Layout/planning
Felling®
Skidding
Hoe chueking
Processing
Loading

Group selection
1.73
3.35
5.00
1.02
1.08
4.75

Group retention
1.16
3.21
3.53
0.00
1.05
4.44

Total cost
16.93
13.39
All costs and productivities are reported for scheduled machine hours.
"Combined weighted average costs of manual and mechanized felling

Clearcut
0.45
3.49
5.46
1.17
1.21
4.18
15.96

64

The highest eosts were observed in the group selection treatment as a result of having steep
f
slope conditions and long skidding distances similar to that of the clearcut while having the
added constraints to skidding and felling as a result of treatment. These constraints caused
mechanical delay for the skidder and resulted in the feller buncher becoming high centred on
an existing log. In addition the planning and layout eosts were highest, $1.73/m^, in the
group selection because of the need to designate removal patches and skid trails compared to
the group retention, where retention patches and skid trails were easy to mark due to gentle
terrain, and the clearcut, where only the boundary and main skid trail were laid out and
marked.

The results and discussion presented here were based upon treatment units ranging in size
from 3.6 ha to 7.4 ha. According to the final volume data, the merchantable volume per
hectare is greater in the group retention treatment than in the other treatments due to a
slightly lower defect percentage, 53% versus 55% in the group selection and 68% in the
clearcut treatment. This defect variation results in a merchantable volume differences
between the treatments. As a result of this higher merchantable volume, the group retention
treatment has lower planning and layout, felling, skidding, processing, and loading costs than
the group selection or clearcut.

If the merchantable volume per tree was standardized (Im^/tree) in each treatment and the
number of harvested trees in each treatment remained constant, the group retention
harvesting system would cost $I4.33/m^ due to a decrease in merchantable volume per piece
(Table 40). This is an increase of SQ.BSW. The group selection costs would also increase

65

by $0.99/m^ to $18.38/m^ as a result of a decrease in merchantable volume per piece. The
cost of the clearcut unit would decrease by $1.4 5 W due to an increase in average piece size
of 0.09m^. The group selection and clearcut costs would also decrease by $ 1.07/m^ and
$1.06/m^, respectively if slopes had not required the use of an excavator for hoe chucking.
Skidding costs would decrease by 25% if the average skidding distances in the clearcut and
group selection treatments was the same as that in the group retention.

Table 40 Summary of Minnow total costs ($/m^) given a standardized merchantable
volume per stem of Im^ ^
Silvicultural treatment
Layout/planning
Felling ®
Skidding
Hoe chucking
Processing
Loading
Total cost

Group selection
L82
3.19
527
1.07
1.13
5.08

Group retention
1.24
3.00
328
0.00
1.13
4.67

Clearcut
0.41
183
4.98
1.06
1.10
3.80

17.56

1182

15.18

“Combined weighted average costs of manual and mechanized felling
5.2.4

Landing Activity

According to the activity sampling, primary transportation was delayed by loading and
manual processing on the landing 3.8% to 9.1% of the scheduled operating time (Table 41
and Appendix 14). These delays resulted in the skidding cost being increased not only for
the skidder but also for the loader and bucker as less wood was available for processing,
sorting, and loading over the same period of time, than if no delays were to occur. The
skidding delay on the landing can easily be avoided through better communication and
coordination of activities. In the different treatments, the bucker was waiting for timber to
process 13% to 33% of the scheduled operating time. The loader was waiting less time for
timber to process, 3% to 12% of the scheduled operating time, as other tasks such as loading

66

trucks or clearing slash or debris could be completed after sorting and decking was
completed. The implementation of another skidder on the sites would increase manual
processing and loading efficiency by a minimum of 3% but would cause a greater increase in
the skidder delay time due to the harvesting components becoming largely unbalanced.

Table 41 Summary of Minnow landing activity sampling
Silvicultural treatment_______ Group selection
Skidder
Loader
Bucker

Skidder/yarder
Loader
Bucker

5.2.5

Delayed
Productive
Delayed
Productive
Delayed
Productive
Delayed
Productive
Delayed
Productive
Delayed
Productive

231
5T69
18.15
41.85
28.15
32T5

Group retention
Time (min)
2.62
5738
12,62
4738
19.54
40.46

4
96
30
70
46
53

Time (%)
4
94
21
79
33
67

Clearcut
5.44
54.56
15.41
44.59
28.64
31.36
9
91
26
74
48
52

Stand Damage

There is no significant difference in the amount of stand damage between the three
treatments (Table 42). Stand damage in all treatments was found within 5 meters of harvest
features. The skid trails were dominated by skid trail creation and skidding origin stand
damage, or stem and root type damage. Damage on patch, block and opening boundaries
was a combination of both skidding and mechanical felling damage, or stem and crown type
damage. In the majority of cases, the boundary damage (openings, patch and block
boundaries) could have been avoided through better placement of bunches or improved
felling practices in regards to swinging. It was a common practice by the buncher operator to

67

place bunches of timber outside or on the edge of the boundary resulting in timber outside of
the harvest area being damaged if not by the felled trees placement then by the removal of
those bunches by the skidder. Stem damage on the skid trails occurred at the funnel points in
the boundary or on the downhill side of a skid trail when the trail was not level. This could
easily be avoided through either the creation of level skid trails or the use of artificial tree
protection such as rub logs on the side of the skid trails or the use of rub trees which are
removed after harvest. Increased damage was also found on skid trail comers and thus these
comers should be placed in harvest patches to provide extra area for the timber to swing.
According to Pavel (1999), in the group selection treatment 14 trees along the skid trail, 18
trees in the patch opening and 14 trees at the meeting of the two features would not be
considered acceptable residual crop tree while 17 trees on the block boundary and 4 patch
boundary trees in the group retention treatment and 13 trees along the clearcut were
considered unacceptable.

68

Table 42 Minnow stand damage summary
Silvicultural
treatment
Feature

Group selection
Skid trails Openings

Group retention
Both

Block
boundary

Clearcut

Patch
Boundary
boundary

Damage summary
No. of sampled trees
No. of injured trees
% of sampled trees®
% of residual stand’’
No. injuries/tree

539
25
4.6
0.9
1.9

985
34
3.5
1.3
1.1

218
21
9.6
0.8
2.0

538
26
4.8
n/a
2.2

534
17
3.2
1.3
1.9

753
26
3.5
n/a
1.6

Average size
Width (cm)
Length (cm)
Area (cm^)
Height (cm)^

13.8
34x5
538.1
103.6

15.5
3&9
675.4
124.5

15.3
4Z3
843.0
140.5

12.9
41.7
668.7
307.3

10.6
222
250.6
178.9

14.8
428
859.1
248.5

Percent of total damage**
Stem
88.0
94.1
100
90.5
932
932
Stem and root
0
12.0
4.9
0
0
0
Root
0
0
0
0
0
0
Crown
0
0
0
6.7
9.5
6.8
®Sampled trees = sample population
*’Residual trees = total population - calculated from cruise and harvesting data
Measured from base of tree to middle of damage
Damage classes: Stem - Stem damage only, Stem and root - Stem and root damage combined,
Root - Root damage only, and Crown - All crown damage.

69

5.3

General Discussion

5.3.1 Planning and layout
As expected the lowest planning and layout costs were observed in the ground-based
clearcuts, followed by the cable clearcut, group retention treatment, and finally group
selection treatments (Table 5, 25 and 43). The need for deflection line in the cable treatment
made it more expensive than a ground-based clearcut. In the group retention, higher layout
costs than a ground-based clearcut was due to the need to mark the leave tree patches and
cruise requirements. The layout in the group selection treatments was the most expensive in
both locations due to the need to designate and mark patches, skid trail locations and greater
block perimeters than in the other treatments. In hindsight, only the outer edge of selection
or retention patches could have been marked, reducing the layout costs. Marking colours
should be “colour blind” friendly as roughly 10% of the male population is color blind (Neitz
et al, 1989), this will ensure appropriate trees are retained or removed. Colours such as red
and greens should be avoided. The layout costs were lower for the group selection treatment
in Minnow over that of East Twin. This may be attributed to the increased experience of the
crew, having implemented the layout after observing the harvesting of East Twin.

Table 43 Planning and layout costs per hectare^
Location
Harvesting svstem
Silvicultural
treatment

East Twin
Ground-based
Cable
Group
Clearcut Clearcut
selection

Minnow
Ground-based
Group
Group
Clearcut
selection
retention

Total cost ($)
2045.74
1923.75
245.31
2285
Treatment area (ha)'
8.7
1.1
11.2
6.7
Harvested area (ha)'
2.1
1.1
6.7
3.6
Treatment area ($/ha)
221.12
223.01
305.33
204.02
Harvested area ($/ha)
916.07
223.01
305.33
634.72
'Harvest and treatment area provided by the BC MOF Cruise reports

2178.22
10.7
6.1
203.57
357.09

1201.31
7.4
7.4
162.34
162.34

70

Sensitivity analysis showed that tree size expressed as merchantable volume has a large
effect on planning and layout costs (Figure 6). Planning and layout costs in the group
selection at East Twin would have been 1.6 times higher if the merchantable volume per tree
was the same as in the clearcut at Minnow. In addition, maximizing the commercial volume
per stem can also reduce the total costs.
7.00

6.00

I

5.00

1
^

4.00

■O

C 3.00

g
C

I

D .

2.00

1.00

-*-0.00
0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2

Merchantable Volume per Tree (m )
“ E a s t T w in C a b le C le a rc u t
M in n o w C le a rc u t

X

E a s t Tw in C le a c u t

- E a s t Tw in G r o u p S e le c tio n

M innow G ro u p R e te n tio n

- M in n o w G r o u p S e le c tio n

Figure 6 Sensitivity analysis of planning and layout costs versus merchantable volume
per tree
5.3.2

Felling

In all but one case, the Minnow group retention treatment, manual felling resulted in the
lowest cost ($/m^) as result of high hourly production (Table 7, 27, and 29; Figure 7). While

71

mechanized felling was utilized at Minnow, manual felling was utilized to fell trees on
steeper slopes (>35%), due to limited traction, and for large solid spruce trees, as multiple
cuts and pushing would have resulted in unnecessary stump pull and butt shatter. As such,
observed manual felling costs in Minnow were higher than those in East Twin due to the
spread-out locations of the trees to be felled; this was especially the case for the Minnow
group retention treatment. While mechanized felling costs were slightly greater, safety was
improved as increased butt flare in cedar in combination with butt rot can make directional
felling difficult and at times dangerous. In addition, mechanized felling resulted in increased
skidding productivity (Table 11 and 31).
7.50

6,50

5.50

% 4.50

3.50

2.50

1.50

0.50
0.5

0.6

0.7

0.8

0.9

1

1. 1

1.2

1. 3

1. 4

1. 5

1. 6

1. 7

1.8

1. 9

2

Merchantable Volume per Tree (m )
- M a n u a l F ellin g E a s t T w in C a b le C le a rc u t

- M a n u a l F ellin g E a s t Tw in C le a rc u t

- M e c h a n ic a l F ellin g M in n o w C le a rc u t

- M e c h a n ic a l F ellin g M innow G r o u p R e te n tio n —e — M e c h a n ic a l F ellin g M in n o w G r o u p S e le c tio n

- M a n u a l F ellin g M in n o w C le a rc u t

- M a n u a l Felling M in n o w G r o u p R e te n tio n

—O — M a n u a l F ellin g E a s t T w in G r o u p S e le c tio n

—

Ma n u a l F e llin g M in n o w G ro u p S e le c tio n

Figure 7 Sensitivity analysis of observed felling costs versus merchantable volume per
tree

72

Significant variables that affected delay-free eyele time for mechanical and manual felling
varied (a-0.05; Table 8 and 28). While skid trail designation, tree species and treatment had
an effect on the total productive time for manual felling at East Twin, they had no significant
effect on mechanized felling at Minnow. The reverse can be said about slope and multiple
cuts. Because tree diameter measurements were only collected for the cable clearcut
treatment, as a result of safety and manpower constraints, the contribution of tree diameter to
felling productivity is limited to the cable treatment; however, we suspect that the
observation will also be true for other treatments. In the case of the mechanized felling, the
effect of diameter may play a lesser role as the actual cutting times only varied from 1.2 to
34.2 seconds, averaging 6.1 seconds per tree while in the manual felling treatments cutting
times varied from 3.0 to 290.4 seconds averaging 60.3 seconds.

5.3.3

Primary Transportation

5.3.3.1

Skidding

Skidding productivity was greatest in the Minnow treatments (Table 11 and 31), however due
to high ownership costs of the grapple skidder at Minnow, the East Twin treatments had
lower costs with the exception of the Minnow group retention treatment. Higher productivity
in the Minnow group retention treatment was due to the low skidding distance and gentle
slope. A given a standard merchantable volume per tree, the grapple skidder had a lower cost
than line skidder even with a higher hourly cost (Figure 8). Given a standardized skidding
distance and merchantable volume per stem, the grapple skidder was still the most cost
effective (Table 44). The East Twin clearcut had a higher standardized cost due to

73

proportionally higher travel times than that of the East Twin group selection and a greater
cubic meter per piece.

13,50

11.50 --

9.50

I

I

7.50

5.50

3.50 -

1.50
0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

Merchantable Volume per Tree (m )
- • - S k id d in g E a s t Tw in C ie a rc u t
S k id d in g M in n o w G r o u p R e te n tio n

- Q - S k id d in g E a s t Tw in G r o u p S e ie c tio n

S k id d in g M in n o w C ie a rc u t

—O —S k id d in g M innow G ro u p S e ie c tio n

Figure 8 Sensitivity analysis of skidding eosts versus merchantable volume per tree

74

Table 44 Skidding costs given a standardized skidding distance of 100 meters and
merchantable volume per stem of Im^ ^
Location
Equipment utilized

1

Minnow
Grapple skidder

East Twin
Line skidder

Silvicultural treatment

Group
selection

Clearcut

Group
selection

Group
retention

Clearcut

Net. volume per turn (m^)
Total cycle time (min)

&86
17.86

4.35
16.87

4.83
10.21

4.60
&34

5^3
10.45

Volume / hour (m^/hr)
Hourly cost ($/hr)

19.69
89.74

15.47
89.74

2&38
116.26

33.09
116.26

32.33
116.26

Skidding cost ($/m^)
A1 . A_______ f ______ 1.

4.56

5.80

4.10

3.51

3.60

Unlike with felling, the significant variables that affected delay-free cycle time for both
grapple and line skidding varied little (Table 12 and 32). Slope did not play a significant role
in line skidded treatments while it had a significant impact on grapple skidder cycle time.
Skid trail designation did not have a significant effect on either skidding method.

5.3.3.2 Yarding
As expected a cable harvesting system was the most expensive method of primary
transportation used to harvest a clearcut treatment (Table 11, 14, and 31). This cost
difference ($2.28/m^) between Minnow clearcut and the East Twin cable unit was due to
dissimilarity in tree piece size. With a standardized piece size of Im^ the yarding cost climbs
to $1 1.37W and the difference grows to $6.39W (Figure 9).

75

24.00

22.00

20.00

18.00

16.00

14.00

s: 12.00

g

10.00

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

Merchantable Volume per Tree (m®)
- Y a r d in g E a s t T w in C a b le C ie a rc u t

- S k id d in g E a s t T w in C ie a rc u t

S k id d in g M innow C le a rc u t

Figure 9 Sensitivity analysis of clearcut yarding and skidding costs versus
merchantable volume per tree

The independent variables that affect yarding cycle time are similar to those of the skidder
treatments (Table 12, 15 and 32). Yarding distance and number o f logs yarded had an impact
on cycle time while similar to the East Twin ground-based units, slope had an insignificant
effect.

5.3.4 Processing
Processing for all sites was manually completed using a chainsaw at the landing. The
primary consideration was to maximize value. Balanced harvest components allowed for the

76

Minnow group selection and retention units to have the lowest processing costs (Table 16,
24, 34, and 41). A standard piece size of Im^ intensifies this result (Figure 10).
4.00

3.50

3.00

® 2.50

2.00

1.50

1.00

0.50
0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

Merchantable Volume per Tree (m )
P r o c e s s in g E a s t T w in C a b le C le a rc u t
-A— P r o c e s s in g M in n o w C le a rc u t

P r o c e s s in g E a s t Tw in C le a rc u t

—O — P r o c e s s i n g E a s t Tw in G r o u p S e le c tio n

P r o c e s s in g M innow G r o u p R e te n tio n

—e — P r o c e s s i n g M in n o w G r o u p S e le c tio n

Figure 10 Sensitivity analysis of processing costs versus merchantable volume per tree

Processing over mature western red cedar presents a number of challenges. This species is
known for pocket and butt rot and as such requires extra steps be taken during manual
processing. During processing, multiple cuts at 0.75m intervals were required to determine
where the timber was eommercially valuable. As increased merchantable volume decreased
the cost, it was important to process the cedar for saw logs and post and rail timber. In the
East Twin group selection treatment, additional processing of cedar for post and rail timber

77

could have increased the merchantable volume by as much as 0.60 m^/ tree, dropping the
processing costs by $0.5 i W and resulting in a total harvesting cost of SlO.VSW. Hemlock,
spruce, and subalpine fir generally did not have any decay, thus was faster to process for the
bucker.

I?

Figure 11 Pocket and ring rot in western red cedar

5.3.5 Loading
Loading costs appear to be independent of treatment and more dependent on a balanced
harvesting operation and volume per tree (Table 23 and 41). The Minnow treatments had the
loader being productive on the landing 69.7% to 79.0% of the time while on the East Twin
treatments, the front-end wheel loader was only productive 46.7% to 47.5% of the time. The
hydraulic loader was productive 71.3% of the time for the cable treatment but due to higher
ownership costs had a higher cost per m^ (Table 18 and 36). When standardized to a uniform

78

piece size, the Minnow treatments have the lowest loading costs followed by the East Twin
ground-based treatments and finally the cable unit (Figure 12).
15.00

13.00

11.00

9.00

ê
at

7.00

Q

5.00

3.00

1.00
0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

Merchantable Volume per Tree (m )
- L o a d in g E a s t Tw in C a b le C le a rc u t
■'Loading M in n o w C ie a rc u t

L o a d in g E a s t Tw in C ie a rc u t

—O —L o a d in g E a s t Tw in G r o u p S e le c tio n

“ ^ L o a d i n g M innow G ro u p R e te n tio n

—0 — L o a d in g M in n o w G r o u p S e ie c tio n

Figure 12 Sensitivity analysis of loading costs versus merchantable volume per tree

5.5.6 Summary o f Harvesting Costs
Treatment, machinery utilized, skidding/yarding distance, yarding road changes, and the
balance of operations can all affect harvesting costs, however net merchantable volume per
tree can have also have an affect (Ashe, 1916; Lynford, 1934; Mann and Mifflin, 1979;
Kluender et al., 1997). Once the merchantable volume per piece is standardized, the
harvesting costs with a semi-mechanized system have a lower cost than that of a

79

conventional system for the same treatment type (Figure 13). Besides additional layout
requirements, the group retention treatment had harvesting costs similar to that of a clearcut.
This was expected as the retention treatment had patch spacing that was at two tree lengths
apart and as a result had little or no effect on felling or skidding productivity. The cable
clearcut had the highest harvesting cost.
50.00

45.00

40.00

E 35.00

Ü

30.00

25.00

aU 20.00
15.00

10.00

0.5

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2

Merchantable Volume per Tree (m^)
- f — E a s t Tw in C a b le C le a rc u t

Ml

E a s t Tw in C le a c u t

E a s t Tw in G r o u p S e le c tio n

"is " M innow C le a rc u t

X

M innow G ro u p R e te n tio n

M in n o w G ro u p S e le c tio n

Figure 13 Sensitivity analysis of total harvesting costs versus merchantable volume per
tree

80

5. 3.7

Stand Damage

Stand damage in the East Twin clearcut units was minimal and the damage present was on
the lower portion of the stem, signifying skidding/yarding damage (Table 24). This reduced
felling damage was the result of the felling and skidding/yarding practices utilized, trees were
felled downhill or into openings and top choked. In the Minnow treatments trees were felled
uphill and bunched into groups to facilitate the use of a grapple skidder. This resulted in
increased felling and skidding damage on boundary features (Table 42). On site observations
confirmed this while it was noted that felled trees rubbed against the residuals while
swinging the feller buncher. This was confirmed by damage being located higher on the
stem than possible from skidding. This damage could have been reduced by changing feller
buncher swinging and felling practices and occasionally top skidding.

As expected, stand damage was greatest along skid trails or at the opening of harvest patches.
In the case of the East Twin group selection treatment this damage was partially the result of
the creation of bladed skid trails and two sharp corners. While damage could be decreased
through the use of rub structures or an incentive program, (Bennett, 1993; McNeel and Dodd,
1996; Langeson, 1997; Matzka, 1998; Kosicki, 2000a) damage could also be reduced by
laying out skid trails as straight and flat as possible and placing skid trail corners within
harvest features. This would not only remove the costs of these rub features but likely
improve skidding cycle times and thus productivity.

While stand damage did occur in all treatments, as the timber in the treatments is already
over mature and contains but and pocket rot, the introduction of pathogens is negligible to

81

fibre quality or mortality. In all cases damage to the stem was also not severe enough to
result in mortality. There was a concern regarding wind firmness and corresponding safety
in several cases as the result of root damage from the creation of bladed trails, yet two years
after harvest, all trees with root damage were still standing. Stand damage to remaining
timber and to block boundaries over and above approved limits may result in penalties or
prosecution (BC Ministry of Forests and Range, 2002).

5.3.8

Operational Implications

According to the study results, a ground-based group retention treatment can be as cost
effective as a ground-based clearcut. This is as expected as the group retention treatment is
operationally similar to a clearcut with reserves. Group selection units still continue to be
more costly to harvest than even cable units. An opportunity cost of the timber that is left
behind in reserves in partial cutting must be considered, however without partial cutting
access to timber lands may be reduced, resulting in an increased opportunity cost. Partial
cutting will provide long term access to fibre on crown lands in the Robson Valley that will
be maintained if not improved over current levels. The use of partial cutting can be
promoted through stumpage allowances, a market based system, packaging harvest units, and
legislation.

Stumpage allowances will reduce the direct cost of fibre, however, a market based system
will result in self regulating fibre costs that reflect market value and adjust for alternative
silvicultural systems. While greater use of fibre into alternative products may result from a
market based system, legislation may be needed to change log grades to better reflect the

82

quality of timber or raise waste and residue penalties to promote improved utilization of poor
quality fibre. The current BC stumpage system classifies timber as either a saw log or
pulpwood grade (Ministry of Forests, 1995). This system is not suitable for over mature
western red cedar from a utilization standpoint as contractors are not required to remove the
pulpwood as no nearby processing facilities exist, even though alternative processing
facilities for low grade fibre, such as post and rail, exist. If a greater percentage of fibre is
recovered, the harvesting cost per cubic meter will decrease. While requiring licensees to
partial cut a through legislation is an option, packaging favoured clearcut units with less
preferred partial cut units is another option. Packaging the units at a flat cost, below that of
traditional clearcuts would entice the licensees into partial cutting. Long term this would
improve partial cutting practices and lower costs, as illustrated in the reduced planning and
layout costs in the Minnow group selection treatment.

From a stand damage standpoint, steps can be taken to further reduce stand damage, however
in over mature stands where the primary goal of retention is for stand structure not
regeneration or the maintenance fibre quality, damage that does not result in mortality may
be considered to be of limited consequence, providing the safety of humans in the stand is
not impacted. Root damage has a significant effect on wind firmness and as such must also
be considered in the context of human safety (Stathers et. al., 1994).

Social and environmental goals achieved by partial cutting, including visual quality,
recreational opportunities, and wildlife habitat, must be considered and valued based on
retention levels. From a tourism perspective, visual; quality and recreational opportunities

83

are important in the Robson Valley (Moon et al., 2004). The area is marketed as a hub for an
infinite variety of outdoor recreation opportunities with a range of micro-climates from
rainforest to high alpine, where flora and fauna, large and small are abundant
(http://mcbride.ca/).

Sheppard et al. (2004) found that visual quality objectives could easily be achieved through
partial cutting. According to a public preference survey, retention treatments have a 70%
preference over maximum modification treatments, while partial retention treatments have a
65% preference over maximum modification treatments (BC Ministry of Forests, 1997).
According to the criteria (BC Ministry of Forests, 1997), retention, partial retention, and
maximum modification treatments are equivalent to the group selection, group retention and
clearcut treatments, respectively, in this study.

The retention of stand structure and islands of habitat along with an increased edge effect
will maintain traditional old growth attributes required by species, such as woodland caribou,
while promoting habitat for other species of flora and fauna. The Northern Rockies
ICH/Silvicultural Systems Project will continue to monitor the effects of various partial
cutting regimes on short-term and long-term stand growth and development, loss and
creation of stand structural biodiversity attributes (wildlife trees and course woody debris),
windthrow, regeneration, and tree mortality(Jull et al., 2002). This long term monitoring will
help to put a financial value on various level of partial cutting.

84

5. 3.9

Suggestions for Future Harvesting Operations

Partial cutting less often used in the interior of BC and specifically cedar dominant stands
due to the perceived additional costs over clearcutting. As partial cutting becomes more
common place, planning, layout, and harvesting costs will continue to decrease as operator
knowledge increases. Based on this study, the following general suggestions may improve
both clearcut and partial cut harvest of interior cedar stands:

1. Mark only the outer edge of retention or selection patches.

2. Mark patches and boundaries with colour blind friendly colours, red and greens
should be avoided.

3. Improved skid trail layout; straight and level with any comers located with harvest
openings will reduce stand damage, eliminate the need for rub features and associated
costs, while likely improve skidding cycle times and thus productivity.

4. Larger over mature cedar can be mechanically felled by multiple cuts; however this
practice is not suitable for large solid trees due to stump pull.

5. Match cuts when using multiple cuts to fell a tree, it will decrease volume loss during
processing.

6. Felling tree into patches, skid trails, or openings will reduce residual stand damage
especially when used in combination with top skidding.

7. Yarding corridor change time can be greatly decreased through pre planning.

85

8. A balanced harvest operation will result in decreased loading and processing costs

9. Pre work meetings can decrease operational delays

10. Merchantable volume per tree ean have an affect on harvesting costs (Ashe, 1916;
Lynford, 1934; Mann and Mifflin, 1979; Kluender et al., 1997). As such the
merchantable volume per tree can be increased by exploring all possible products for
species being harvested.

11. Stand damage could be deereased through the use of rub structures, (Bennett, 1993;
Matzka, 1998; Kosicki, 2000a), incentive or bonus penalty program (McNeel and
Dodd, 1996; Langeson, 1997), and/or operator education (Matzka, 1998).

12. Root damage can be avoided in partial cuts by not utilizing bladed skid trails.

5.3.10 Opportunities fo r Future Research
This study is part of the Northern Roekies ICH/Silvicultural Systems Project, established to
examine ways of managing ICH and ESSF forests in a manner that would address both
ecological and socio-economic concerns. While this study has provided information on the
harvesting cost, productivity and stand damage for the particular treatments examined, it is
not clear if these results ean be replicated in other cedar dominated stands or if these results
can be applied to other forest types, however general findings may be applicable. In
addition, other harvesting treatments such as cable partial cuts and a conventionally
harvested group retention treatment were not replicated. Further study in regards to patch
and skid trail layout relation to residual stand damage is also recommended.

86

6

Conclusion

This study examined three silvicultural systems utilizing three harvesting systems in over
mature interior cedar hemlock stands in east central British Columbia. Layout costs,
harvesting productivity and costs, and residual stand damage were determined for each
treatment. As expected the planning and layout costs were the lowest in the clearcut
treatments ($0.45/m^-0.68/m^) and followed by the group retention ($1.16/m^) and selection
treatments ($1.73/m^-$2.62/m^). Harvesting costs varied in the conventional system
treatments from $10.95/m^ - $16.09/m^ and from $13.45/m^-$17.37/m^ in the semi­
mechanized system treatments. The cable system had a cost of $15.70/m^. It was expected
that the harvesting costs would be lowest in the ground-based clearcut treatments followed
by the group retention treatments, group selection and cable clearcut. It was also expected
that the semi-mechanized system would be more cost effective than the conventional system.
It was found that the semi-mechanized group retention treatment was the most cost effective.
The semi-mechanized group selection was cheaper than the conventional group selection
treatment due to a higher production rate common with mechanized harvesting operations.
The cable clearcut was the most expensive treatment.

An understanding of the traditional and alternative products that can be derived from the
harvested timber was key in increasing the amount of merchantable volume and reducing the
corresponding harvesting costs. As such it is recommended that all possible product options
be explored prior to processing to ensure the merchantable volume is maximized.

87

Stand damage was greatest in the group selection treatments; however mechanized felling
showed a significant stand damage increase over manual felling as a result of felling
practices. This was not expected as mechanized felling according to the literature results in
greater control of the felled stem. Had the tree been felled toward the inside of harvest
openings or skid trails this damage would have been greatly reduced. As expected, grapple
skidding resulted in a lower level of stand damage than that of line skidding, this however
may have been the result of poor skid trail layout and design in the line skidder treatment.

Partial cutting of cedar dominated stands needs to proceed with an increased emphasis on
layout, alternative silvicultural trials, alternative commercial products, and the reduction of
stand damage. This will ensure the continuation of commercial forestry while promoting
ecological and socio-economic concerns.

88

7 Literature Cited
Aho, P.E.; Fiddler, G.; Filip, G.M. 1983. How to reduce injuries to residual trees during stand
management activities. USDA Forest Service. Pacific Northwest Forest and Range
Experiment Station. General Technical Report, PNW-156. June 1983. 17 pp.
Amott, J.T.; Beese, W.J. 1997. Alternatives to clearcutting in BC Coastal Montane Forests.
Forest Chronicle. Vol 73(6). 670-678pp
Ashe, W.W. 1916. Cost of logging large and small timber For. Quart. Vol. 12. 221-452 pp.
Bennett, D.M. 1997. Partial cutting in mountainous old-growth forests in coastal British
Columbia; harvesting productivity and cost, and residual stand impacts. FERIC, Vancouver,
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Bennett, D.M. 1993. Partial cutting in a second-growth Douglas-fir stand in coastal British
Columbia: productivity, costs, and soil Impacts. FERIC Publication: Wood Harvesting,
Technical Note TN-199. 12 pp.
Boswell, B. 2001. Partial cutting with a cable yarding system in coastal British Columbia.
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Publications Inc., Victoria BC. Publication #120BC.
British Columbia Ministry of Forests. 1996a. Cruising Manual. April 1, 1996 Amendment.
Crown Publications Inc., Victoria BC. Publication #106BC.
British Columbia Ministry o f Forests. 1996b. Draft field guide insert for site identification
and interpretation for the southeast portion of the Prince George Forest Region. June 1996.
Prince George Forest Region, BC Ministry of Forests, Prince George, BC., 1011 4* Avenue,
Prince George, BC V2L 3H9.
British Columbia Ministry of Forests. 1996c. Draft field guide insert for site identification
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BC Ministry of Forests, Prince George, BC., 1011 4* Avenue, Prince George, BC V2L 3H9.
British Columbia Ministry of Forests. 1997. Visual Impacts of Partial Cutting: Summary
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Inc., Victoria BC.
British Columbia Ministry of Forests and Range. 2002 Forest and Range Practices Act
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Bruno, J.C. 1979. Design and layout considerations in smallwood, partial-cut skyline logging
operations. A thesis for Master of Science, University of Washington. 104 pp.
Daigle, P.W. 1995. Partcuts: a computerized annotated bibliography of partial-cutting
methods in the Pacific Northwest (1995 Update). Forestry Canada; British Columbia
Ministry of Forests. 25 pp.
DeLong, C.; Tanner, D.; Jull, M. 1994. A field guide for site identification and interpretation
for the northern Rockies portion of the Prince George Forest Region. Land Management
Handbook 29. British Columbia Ministry of Forests, Research Branch. 31 Bastion Square,
Victoria, BC. 141 pp.
Dunham, M.; Gillies, C. 2000. Skyline partial cutting in the Interior Cedar-Hemlock
biogeoclimatic zone; harvesting productivity and cost. FERIC, Vancouver, BC. Advantage.
Vol. 1 (40): 16 pp.
Dunham, M.T. 2001. Planning and layout costs I: group selection and clearcut prescriptions.
FERIC, Vancouver, BC. Advantage. Vol. 2 (22): 6 pp.
Dunham, M.T. 2004. Planning and layout costs III: field engineering for a group selection
prescription. FERIC, Vancouver, BC. Advantage. Vol. 5 (39): 4 pp.
Gardner, R.B. 1980. Skyline yarding productivity under alternative harvesting prescriptions
and levels of utilization in larch-fir stands. USDA For. Sew. Intermount. For. Range Exp.
Sta., Ogden, Utah. Res. Pap. INT-247.35 pp.
Gillies, C. 2002 Ground-based harvesting in a partial cutting operation in interior British
Columbia. FERIC, Vancouver, BC. Advantage. Vol. 3 (14): 16 pp.
Han, H-S.; Kellogg, L.D. 2000. A comparison of sampling methods for measuring residual
stand damage from commercial thirming. International Journal of Forest Engineering. Vol. 11
(1). 63-71 pp.
Han, H-S.; Renzie, C. 2005. Effect of Ground Slope, Stump Diameter, and Species on Stump
Height for Feller-Buncher and Chainsaw Felling. International Journal of Forest Engineering.
Vol. 16 (2): 81-88 pp.
Hedin, I.B.; De Long, D.L. 1993. Comparison of harvesting phases in a case study of partialcutting systems in southwestern British Columbia. FERIC, Vancouver, BC. Special Report
SR-85. 16 pp.
Hedin, I.B. 1994. Shelterwood harvesting in coastal second-srowth Douglas-fir. FERIC,
Vancouver, BC. Technical Note TN-216. 10 pp.

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Howard, A.F.; Rutherford, D.; Young G.G. 1996. Optimal skyline corridor spacing for partial
cutting in second-growth stands of coastal British Columbia. National Research Council
Canada. Reprinted from Canadian Journal of Forest Research. Vol. 26. 368-375 pp.
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silvicultural systems in Interior Wetbelt ESSF and ICH forests. Workshop Proceedings, June
10th to 12th, 1997. University of Northern British Columbia, Prince George, BC. 71 pp.
http://wetbelt.unbc.ca/docs/1997%20Wetbelt%2DWorkshop%20Proceedings%20rEcosvstem
%20Dvnamics%20and%20Silv%20Svs').pdf
Jull, M.; Stevenson, S.; Rogers, B.; Sanborn, P.; Eastham, A.; Sagar, B.; Beaudry, L. 2002.
Establishment Report (Second Approximation): Summary of Harvest Treatments,
Monitoring Installations, and Overview of Pre- and Post-Harvest Conditions. University of
Northern British Columbia Forest Renewal BC Research Project Number: OP96081-RE
(1996-2001) and OPR02006-09 (2001/02).
http://wetbelt.unbc.ca/docs/NWetbelt-Estab-Report 2nd-Approx-Post-harvest-April%20022.pdf
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Forestry prescriptions. In Proceedings: Conference on Forestry Operations in the 1990s:
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felling, and skyline yarding costs between clearcutting and five group-selection harvesting
methods. Western Journal of Applied Forestry. Vol. 11 (3) 90-96 pp.
Kemmler, S. 2000. Helicopter logging project management course. Malispina University
College, Forestry Extension Program. Nanaimo, BC. Handbook. 35pp.
Kluender, R.A.; Stokes, B.J. 1994. Productivity and costs of three harvesting methods.
Southern Journal of Applied Forestry. Vol. 18 (4) 168-174 pp.
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Kohm, K.A.; Franklin, J.F. 1997. Creating a Forestry for the 21st Century: The Science of
Ecosystem Management. Island Press, Washington, DC. 475 pp.
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riparian zone. FERIC, Vancouver, BC. Advantage. Vol. 1 (19) 28 pp.

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Kosicki, K.T. 2000b. Productivity and cost of an Owren 400 hydrostatic yarder. FERIC,
Vancouver, BC. Advantage. Vol. 1 (35). 20 pp.
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clearcuts, patch cuts and single-tree selection cuts: Rennell Sound trials. FERIC, Vancouver,
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93

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94

8

Glossary of Harvesting Terms

Butt’n top loader
A hydraulic loader that utilizes a special grapple to grasp logs in the middle. Out rigger arms
on the grapple balance the logs. The grapple is able to turn the logs end for end. This
facilitates truck loading by equalizing the payload. The grapple is designed to handle smaller
logs.

Backspar
A tree or machine rigged at the back end of the work area to provide lift for yarding lines. It
is also knovm as a tail spar.

Choker
A wire rope noose for hooking the logs to a yarder carriage or skidder.

Conventional harvesting system
Conventional system is a ground-based system that utilizes manual felling, line skidding,
manual processing at the landing and mechanical loading

Heel-boom loader
A hydraulic loader that grasps logs at the end and using a movable heel, on the grapple,
controls and tilts logs. The grapple is not able to turn logs end for end. and is designed to
handle larger logs.

95

Hoe Chucking
The movement of felled timber with an excavator, using its bucket and thumb, and placing
the timber into bunches.

Hook tender
A hook tender is a person on the hill in cable yarding which uses chokers to attach trees to
the carriage

Semi-mechanized harvesting system
Semi mechanized system is a ground-based system that utilizes mechanical and manual
felling, grapple skidding, manual processing at the landing and mechanical loading

Running skyline
A running skyline system is similar to a skyline system except that the skyline (also knovm
as a haulback line) cable is attached to the far end of the carriage and is used to return the
carriage uphill. The mainline cable is attached to yarder end of the carriage while the
haulback or skyline is attached to the opposite end. From the carriage, the skyline is passed
though a pulley on the tail end of the system and returns to the yarder. The carriage is hung
off of blocks on the haulback line. The weight of carriage and logs are distributed to both the
skyline and mainline cables.

96

Running skyline system, figure from Macdonald, 1999

Skyline (multispan or single)
A skyline system uses a carriage running on a cable (skyline) that is used to partially or
completely lift the logs. The skyline cable supports all the weight load weight while the load
is pulled to the landing by the mainline. Unlike a running skyline system the skyline does
not move. The figure below is a multispan skyline system (Macdonald, 1999). A multispan
system uses intermediate supports to increase the deflection of the skyline cable, while a
single span system has no intermediate supports.

Multispan skyline system, figure from Macdonald, 1999

97

Slack pulling carriage
A slack-pulling carriage allows a yarding line to be pulled to the side of the skyline corridor.,
increasing the capability for lateral yarding. There are a variety of slack-pulling carriages
ranging from line pulled totally by hand to carriages with an internal motor that feeds out the
line.

Stump pull
Stump pull occurs when hinge wood is left in the middle of the stump and pulls fibre fro the
centre of the felled tree during the felling process

Tree felled

M is m a tc h e d

o r In c o m p le te c u t

S tu m p -p u ll lo s s

Stump

Stump pull, figure adapted from Han and Renzie, 2005

98

Appendix 1 - East Twin Harvesting Equipment
Manual fellin:

John Deere 640 D Line Skidder - Ground-based Units

99

Madill J7C Tower Yarder - Cable Unit

I

Homemade Runnm

Carnage

100

Manual Processin

John Deere 644E Front-end Log Loader - Ground-based Units

101

Barko 425 Heel-boom Log Loader - Cable Unit

102

Appendix 2 - Minnow Creek Harvesting Equipment
Timberjack 618 Feller Buneher

Manual Felling

103

John Deere 748E Grapple Skidder

Hitachi EX270LC Excavator

104

Manual Processin
k

•

a

Komatsu WA 320 Front-end Log Loader

*•<(

s * ,x ^

..L.,

105

Appendix 3 - East Twin and Minnow Site Maps
East Twin C reek
&Lct^ A re a (ICHwfâ)

C ]cu r

' omni

0

rm

G ro u n d -b a se d

C le a rc u t

omi=

203

300

S co fe h ü n c e re

U n c u t C o n tro l

G ro u p

S e le c tio n

/

y /
Minnow Creek
Study Area (ICHwk3)
Uncut Control
100% Retention

1 Cut
" Area

Uncut
Area

S cale In m eters

Ripanan
X R eserve.

.

' Group selection^ >
70% Retention

C learcut
0% Retention

Group retention
30% Retention

106

Appendix 4 - Shift Level Forms
M a n u a l F e llin g , D a ily S h if t L e v e l F o r m
U N B C F o re s try

P a rtia l C u t C o s t A n a ly s is S tu d y

Daily Felling Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

S ta rt T im e :

E a s t T w in C a b le C le a r c u t,

E n d T im e :

E a s t T w in G ro u n d B a s e d C le a r c u t, o r
B re a k T im e :

E a s t T w in 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

S n o w in g

R a in

T e m p e ra tu re :

FELLER PRODUCTION
N A M E

H O U R S W O R K ED

TR EES CU T

FELLER #I
F E L L E R #2

M IN U T E S

FE L L E R #

D E S C R IP T IO N O F D E L A Y

O T H E R D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

FE L L E R #

D E S C R IP T IO N O F D E L A Y

C O M M E N T S ( p r o v i d e a n y a d d i t i o n a l i n f o r m a t i o n t h a t h e l p s t o e x p l a i n t h e d a y ’s p r o d u c t i o n )

* Please start a new form when moving to a different block

107

Skidder, Daily Shift Level Form
U N B C F o re s try

P a rtia l C u t C o s t A n a ly s is S tu d y

Daily Skidding Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

O p e ra to r:

E a s t T w in G ro u n d B a s e d C le a rc u t, o r

S ta rt T im e :

E a s t T w in 3 0 % R e m o v a l
E n d T im e :

W e a th e r:

Sunny

C lo u d y

S n o w in g

R a in

B re a k T im e :

T e m p e ra tu re :

SKIDDER PRODUCTION
T o ta l # T u rn s

T o ta l # L o g s

T o ta l # T o p s

D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
TY PE

M IN U T E S

D E S C R IP T IO N O F D E L A Y

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

C O M M E N T S ( p r o v id e a n y a d d itio n a l in f o r m a tio n t h a t h e lp s to e x p la in th e d a y ’s p r o d u c tio n )

D e la y T y p e s :
M e c h a n ic a l - A n y d e la y r e la te d to th e m e c h a n ic a l fa ilu re o f th e s k id d e r
M a in te n a n c e - A n y tim e s p e n t o n r e g u la r m a in te n a n c e o f s k id d e r d u r in g th e s h ift
P e rs o n a l - O p e ra to r r e la te d d e la y tim e
O th e r - S p e c ify n a tu r e o f d e la y in d e s c r ip tio n o f d e la y

* Please start a new form when moving to a different block

108

Yarder, Daily Shift Level Form
UNBC Forestry

Partial Cut Cost Analysis Study

Daily Yarding Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

O p e ra to r:

S ta rt T im e :

E a s t T w in C a b le C le a r c u t

E n d T im e :

W e a th e r:

Sunny

C lo u d y

S n o w in g

R a in

B re a k T im e :

T e m p e ra tu re :

YARDER PRODUCTION
T o ta l # T u rn s

T o ta l # L o g s_

TY PE

M IN U T E S

T o ta l # T o p s

D E S C R IP T IO N O F D E L A Y

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

C O M M E N T S ( p r o v i d e a n y a d d i t i o n a l i n f o r m a t i o n t h a t h e l p s t o e x p l a i n t h e d a y ’s p r o d u c t i o n )

D e la y T y p e s;
M e c h a n ic a l - A n y d e la y r e la te d to th e m e c h a n ic a l fa ilu re o f th e y a rd e r
M a in te n a n c e - A n y tim e s p e n t o n re g u la r m a in te n a n c e o f y a r d e r d u rin g th e s h ift
P e rs o n a l - O p e ra to r r e la te d d e la y tim e
O th e r - S p e c ify n a tu r e o f d e la y in d e s c r ip tio n o f d e la y

* Please start a new form when moving to a different block

109

Manual Bucking, Daily Shift Level Form
U N B C F o re s try

P a rtia l C u t C o s t A n a ly s is S tu d y

Daily Bucking Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

S ta rt T im e :

E a s t T w in C a b le C le a r c u t,

E n d T im e :

E a s t T w in G ro u n d B a s e d C le a rc u t, o r
E a s t T w in 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

B re a k T im e :

S n o w in g

R a in

T e m p e ra tu re :

BUCKER PRODUCTION
N A M E

H O U R S W O R K ED

TR EES CU T

B U CK ER #I
B U C K E R #2

M IN U T E S

B U C K ER #

D E S C R IP T IO N O F D E L A Y

O T H E R D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

B U C K ER #

D E S C R IP T IO N O F D E L A Y

C O M M E N T S ( p r o v id e a n y a d d itio n a l in f o r m a tio n t h a t h e lp s to e x p la in t h e d a y ’s p r o d u c tio n )

* Please start a new form when moving to a different block

110

Loader, Daily Shift Level Form
U N B C F o re s try

P a rtia l C u t C o s t A n a ly s is S tu d y

Daily Loader Production
G E N E R A L IN F O R M A T IO N
O p e ra to r:

D a te

B lo c k :

E a s t T w in C a b le C le a rc u t,

S ta rt T im e :

E a s t T w in G ro u n d B a s e d C le a rc u t, o r
E a s t T w in 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

E n d T im e :

S n o w in g

R a in

B re a k T im e :

T e m p e ra tu re :

LOADER PRODUCTION
T ru ck #

T o ta l# o f L ogs

D e s tin a tio n o f L o a d

T ru ck #

T o ta l# o f L ogs

D e s tin a tio n o f L o a d

D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

TY PE

D E S C R IP T IO N O F D E L A Y

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

C O M M E N T S ( p r o v i d e a n y a d d i t i o n a l i n f o r m a t i o n t h a t h e l p s t o e x p l a i n t h e d a y ’s p r o d u c t i o n )

D e la y T y p e s:
M e c h a n ic a l - A n y d e la y r e la te d to th e m e c h a n ic a l fa ilu r e o f th e s k id d e r
M a in te n a n c e - A n y tim e s p e n t o n r e g u la r m a in te n a n c e o f s k id d e r d u r in g th e s h ift
P e rs o n a l - O p e ra to r r e la te d d e la y tim e
O th e r - S p e c ify n a tu r e o f d e la y in d e s c r ip tio n o f d e la y

* Please start a new form when moving to a different block

111

Manual Felling, Daily Shift Level Form
UNBC Forestry

Partial Cut Cost Analysis Study

Daily Felling Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

S ta rt T im e :

M in n o w C le a rc u t,

E n d T im e :

M in n o w 7 0 % R e m o v a l, o r
B re a k T im e :

M in n o w 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

S n o w in g

R a in

T e m p e ra tu re :

FELLER PRODUCTION
N A M E

H O U RS W O R K ED

TR EES CU T

F E L L E R #1
F E L L E R #2

M E C H A N IC A L D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

FE L L E R #

D E S C R IP T IO N O F D E L A Y

O T H E R D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

FE L L E R #

D E S C R IP T IO N O F D E L A Y

C O M M E N T S ( p r o v i d e a n y a d d i t i o n a l i n f o r m a t i o n t h a t h e l p s t o e x p l a i n t h e d a y ’s p r o d u c t i o n )

* Please start a new form when moving to a different block

112

Skidder, Daily Shift Level Form
UNBC Forestry

Partial Cut Cost Analysis Study

Daily Skidding Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

O p e ra to r:

M in n o w C le a r c u t,

S ta rt T im e :

M in n o w 7 0 % R e m o v a l, o r
M irm o w 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

E n d T im e :

S n o w in g

R a in

B re a k T im e :

T e m p e ra tu re :

SKIDDER PRODUCTION
T o ta l # T u rn s

M IN U T E S

T o ta l # L o g s

TY PE

T o ta l # T o p s

D E S C R IP T IO N O F D E L A Y

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

C O M M E N T S ( p r o v id e a n y a d d itio n a l in f o r m a tio n t h a t h e lp s to e x p la in th e d a y ’s p r o d u c tio n )

D e la y T y p e s:
M e c h a n ic a l - A n y d e la y r e la te d to th e m e c h a n ic a l fa ilu r e o f th e s k id d e r
M a in te n a n c e - A n y tim e s p e n t o n re g u la r m a in te n a n c e o f s k id d e r d u rin g th e s h ift
P e rs o n a l - O p e ra to r re la te d d e la y tim e
O th e r - S p e c ify n a tu r e o f d e la y in d e s c r ip tio n o f d e la y

* Please start a new form when moving to a different block

113

Manual Bucking, Daily Shift Level Form
UNBC Forestry

Partial Cut Cost Analysis Study

Daily Bucking Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

S ta rt T im e :

M in n o w C le a r c u t,

E n d T im e :

M in n o w 7 0 % R e m o v a l, o r
B re a k T im e :

M in n o w 3 0 % R e m o v a l

W e a th e r:

Sunny

C lo u d y

S n o w in g

R a in

T e m p e ra tu re :

BUCKER PRODUCTION
N A M E

H O U R S W O R K ED

TR EES CU T

B U C K E R #!
B U C K E R #2

M IN U T E S

B U C K E R #

D E S C R IP T IO N O F D E L A Y

O T H E R D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

B U C K ER #

D E S C R IP T IO N O F D E L A Y

C O M M E N T S ( p r o v id e a n y a d d itio n a l in f o r m a tio n t h a t h e lp s to e x p la in th e d a y ’s p r o d u c tio n )

* Please start a new form when moving to a different block

114

Loader, Daily Shift Level Form
U N B C F o re s try

P a rtia l C u t C o s t A n a ly s is S tu d y

Daily Loader Production
G E N E R A L IN F O R M A T IO N
D a te

B lo c k :

O p e ra to r:

M irm o w C le a r c u t,

S ta rt T im e :

M in n o w 7 0 % R e m o v a l, o r
M in n o w 3 0 % R e m o v a l

W e a th e r:

S u rm y

C lo u d y

E n d T im e :

S n o w in g

R a in

B re a k T im e :

T e m p e ra tu re :

LOADER PRODUCTION
T ru ck #

T o ta l # o f L o g s

D e s tin a tio n o f L o a d

T ru ck #

T o ta l # o f L o g s

D e s tin a tio n o f L o a d

D E L A Y S (G R E A T E R T H A N 10 M IN U T E S )
M IN U T E S

TY PE

D E S C R IP T IO N O F D E L A Y

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

M a in te n a n c e M e c h a n ic a l
P e rso n a l

O th e r

C O M M E N T S ( p r o v id e a n y a d d itio n a l in f o r m a tio n t h a t h e lp s to e x p la in th e d a y ’s p r o d u c tio n )

D e la y T y p e s:
M e c h a n ic a l - A n y d e la y r e la te d to th e m e c h a n ic a l fa ilu r e o f th e s k id d e r
M a in te n a n c e - A n y tim e s p e n t o n r e g u la r m a in te n a n c e o f s k id d e r d u r in g th e s h ift
P e rs o n a l - O p e ra to r r e la te d d e la y tim e
O th e r - S p e c ify n a tu r e o f d e la y in d e s c r ip tio n o f d e la y

* Please start a new form when moving to a different block

115

Appendix 5 - Detailed Time Elements
Dependent and independent variables for timing manual felling
Manual felling
Dependent Variables
Name

Definition

Independent Variables
Name

Definition

Cvcle elements:
stump diameter (cm), taken
when possible

Cut

process of cutting tree

Diameter

Move

process of moving to next
tree

Treatment area

Brush

clearing brush around tree

Tree number

sample number

Wedge

using a wedge to direct
tree during felling

Road method

designated and non­
designated

Shovel

removal o f snow from
around stem

Slope

slope of ground (%)

Reconnaissance

examination of terrain to
determine which tree to
fell next

Species

tree species: western red
cedar, subalpine fir,
Engelmann spruce, western
hemlock

silvicultural treatment:
clearcut, group selection and
group retention

Delavs:
Fuel

fuelling of saw

File

sharpening of saw

Fix saw

repairing of saw

Rest

short break

Walk in or out

travel in or out of work
area

Move equipment
Meetings

Other delays

moving of spare saw or
tools
safety or production
meeting
unexpected delays mechanical, operational,
and personal, details
noted

116

Dependent and independent variables for timing a feller buncher

Feller buncher
Dependent Variables
Name

Definition

Independent Variables
Name

Definition

Cvcle elements:
Cut

process of cutting tree

Treatment area

silvicultural treatment:
clearcut, group selection and
group retention

Move

process of moving to next
tree

Tree number

sample number

Brush

clearing brush around tree

Road method

designated and non­
designated

Push

pushing over of tree by
feller buncher

Slope

slope of ground (%)

Species

tree species: western red
cedar, subalpine fir,
Engelmann spruce, western
hemlock

Bunch

Reconnaissance

grouping of felled stems
examination of terrain to
determine which tree to
fell next

Delavs:
Fuel

fuelling o f feller buncher

Walk in or out

Travel in or out of work
area

Rest

short break

Meetings

Other Delays

safety or production
meeting
unexpected delays mechanical, operational,
and personal, details
noted

117

Dependent and independent variables for timing a skidder equipped with a winch line
Skidder equipped with a winch line
Dependent Variables
Name

Independent Variables
Name

Definition

Treatment area

silvicultural treatment:
clearcut, group selection and
group retention

Turn number

sample number

Travel distance

distance traveled (m)

Definition

Cvcle elements:
Travel empty
Positioning
Line out

travel out to get a turn of
logs
process of moving to next
log or bunch of logs
mainline released from
skidder to facilitate log
choking

Choking

process of choking logs

Road method

designated and non­
designated

Line in

Winding up of mainline to
skidder to facilitate travel

Slope

slope of ground or trail (%)

Travel loaded

travel back to landing with
a load of logs

Chokers

number of chokers used per
turn

Delimbing

removal of tree limbs

Logs

number of trees/logs per turn

Clear trail

clearing trail to facilitate
travel

Trees choked

number of trees choked per
turn

Unhook turn

unhooking chokers

Reconnaissance

examination of terrain to
determine which log or
group of logs to skid next

Delavs:
Fuel

fuelling of skidder

Walk in or out

Travel in or out of work
area

Rest

short break

Meetings
Other Delays

safety or production
meeting
unexpected delays mechanical, operational,
and personal, details noted

118

Dependent and independent variables for timing a grapple skidder

Grapple skidder
Dependent Variables
Name

Independent Variables

Definition

Name

Definition

Cvcle elements:
Travel empty

travel out to get a turn of
trees

Treatment area

silvicultural treatment:
clearcut, group selection and
group retention

Positioning

process of moving to next
log or bunch

Turn number

sample number

Accumulate

grouping of logs into a
bunch

Travel distance

distance traveled (m)

Load

process of closing and lifting
grapple

Travel loaded

travel back to landing with a
load of logs

Unloading

Separate

opening grapple to release
logs
Separating logs after
unloading to facilitate
delimbing and manual
processing

Delimbing

removal of tree limbs

Reconnaissance

examination of terrain to
determine which tree to fell
next

^^hod

designated and non­
designated

Slope

slope of ground or trail (%)

Logs

number o f trees/logs per turn

Delavs:
Fuel

fuelling o f skidder

Clear trail

clearing trail to facilitate
travel

Walk in or out

Travel in or out of work area

Rest

short break

Meetings

safety or production meeting

Other Delays

unexpected delays mechanical, operational, and
personal, details noted_____

119

Dependent and independent variables for timing a running skyline system

Yarder with a running skyline system
Dependent Variables
N am e

Independent Variables

D e fin itio n

N am e

D efin itio n

Outhaul

carriage travels out to get a
turn o f trees

Turn number

sample number

Hooking

process of choking logs

Yarding
distance

distance yarded (m)

Inhaul

carriage travels back to
landing with a turn of logs

Slope

slope o f ground or trail (%)

Unhooking

process of removing chokers
from logs

Chokers

number o f chokers used per
turn

Delimbing

removal o f tree limbs

Logs

number of trees/logs per turn

Cvcle elements:

Delavs:
Setting change

changing yarding corridor

Wait for choker

delay caused by hook tender
on hill

Wait for loader

delay eaused by loader on
landing

Wait for chaser

delay caused by chaser on
landing

Wait for
skidder

delay caused by skidder

Fuel

fuelling o f yarder

Walk in or out

Travel in or out of work area
by hook tenders

Meetings

safety or production meeting

Other Delays

unexpected delays mechanical, operational, and
personal, details noted

120

Appendix 6 - East Twin Machine Costs
CONTRACTOR
OWNERSHIP COSTS

Total Purchase Price (P) $
Expected Life (Y) y
Expected Life (H) h
Scheduled hours/year (h)=(H/Y) h
Salvage value as % of P (s) %
Interest rate (Int) %
Insurance rate (Ins) %
Salvage value (S)=(P*s)/100) $
Average investment (AVI)=((P+S)/2) $
Loss in resale value ((P-S)/H) $/h
Interest ((lnt*AVI)/h) $/h
Insurance ((Ins*AVI)/h) $/h
Total ownership costs (OW) $/h
OPERATING COSTS
Wire rope (we) $
Wire rope life (wh) h
Rigging and radio (re)
Rigging and radio life (rh) h
Fuel Consumption Diesel (F) L/h
Fuel Cost Diesel (fc) $/L
Lube and oil as % o f ftiel (fp) %
Track and undercarriage replacement (Tc)
$
Track and undercarriage life (Th) h
Annual repair & maintenance (Rp) $
Annual operating supplies (Oc) $
Annual tire consumption (t) no.
Tire replacement (tc) $
Operator wages $/h
Hook tender wages
Number of hook tenders
Wage benefit loading (WBL) %
Shift length (si) h
Wire rope (we/wh) $/h
Rigging and radio (rc/rh) $/h
Fuel (F*fc) $/h
Lube and oil ((fp/IOO*(F*fc)) $/h
Tires ((tc*t)/h) $/h
Repair and maintenance (Rp/h) $/h
Track and Undercarriage (Te/Th) $/h
Operating supplies (Oe/h) $/h
Wages and benefits (W*(1+WBL/100) $/h
Prorated overtime
((1.5*W-W)*(sl-8)*(I +WBL/IOO))/sl) $/h
Total operating costs (OP) $/h
TOTAL OWNERSHIP AND OPERATING
COSTS (OW+OP) $/h

John Deere 6400 Caterpillar D6R ■'«•'n Deere 644H Madill 172-5
Drum Tower
UMSÜWm
Loader
Yarder

Barko475B Heel
Boom Loader

246,200
5
10000
2000
30

395,000
5

316,000
5

10000

10000

2000
30

2000
30

900,000"
10
20000
2000
30

10

10

10

10

3
73,860
160,030
17.23

3
118,500
138,250
27.65
6.91
2.07
36.64

3
94,800
110,600
22,12
5.53
29.31

3
270.000
315.000
31.50
15.75
4.73
51.98

544,000
5
10000
2000
30
10
3
163,200
190,400
38.08
9.52
2.86
50.46

15100
2000
13800
4000
40
0.50
15

20
0.50
15

8.00

2.40
27.64

1.66

22
0.50
15

23
0.50
15

22
0.50
15

0.00

20000

0

10000

8,000

0.00
20,000
1,500
2
3,300
25.00

10000
14000
1500

100000
20,000
1,500

10,000
20,000
1,000

25.00

0
12000
1000
2
2300
25.00

25.00

35
8

35
8

35
8

11.00
3.30
3.30
10.00

11.50
3.45

I I 00
3.30
2.30
6.00

25.00
20.00
2
35
8
7.55
3.45
20.00
6.00

10.00
0.80
0.50
33.75

35
8

10.00
3.00

0.75
33.75

7.00
2
0.75
33.75

0.50
33.75

10.00
0.10
0.75
87.75

0.00

0.00

0.00

0.00

0.00

62.10

58.45

56.85

135.60

58.05

89.74

95.09

86.16

187.58

108.51

“ Yarder cost includes the cost for a non-slackpulling carriage.
* Wage Costing: Feller is on a day rate of $400 based on an 8-hour workday and the bucker is on an hourly rate
of $25 per hour

121

Appendix 7 - Minnow Machine Costs

OW NERSHIP COSTS
Total Purchase Price (Pi $
Expected Life (Yi v

Komatsu

Hitaehi

Tim ber Jack

John Deere

618 Feller

748E G rapple

Buneher

Skidder

465,000
5

239.000.00
5
10000
2000
30.00
10
3
71.700.00
83.650.00
16.73
4.18
1.25

355,000.00
5
10000
2000
30.00
10
3
106.500.00
124.250.00
24.85
6.21
1.86

575.000,00
5
10000
2000
30,00
10
3
172.500.00
201.250.00
40,25
10,06
3.02

WA320
Front-end
Log Loader

EX270LC
E xeavator

C aterpillar
D 7H T raetor

Expected Life (Hi h
Scheduled hours/year (hi=(H/Yi h
Salvage value as % o f P (si %
Interest rate (Inti %
Insurance rate (Insi %
Salvage value (Si=(P*si/100i $
Average investment
Loss in resale value ((P-Si/Hi $/h
Interest ((Int*AVIi/hi $/h
Insurance ((Ins*AVIi/hi $/h

10000
2000
20.00
10
3
93,000.00
186,000.00
37.20
9.30
2.79

330.000.00
5
10000
2000
25.00
10
3
82.500.00
206.250.00
24.75
10.31
3,09

Total ownership costs (OW i S/h

49.29

38.16

22.17

3Z M

53.33

OPERATING COSTS
Fuel Consumption Diesel (Pi L/h
Fuel Cost Diesel (fci $/L

30.00
0.50

25.00
0.50

32
0.50

23
0.50

20
30.000.00
5.000.00
86.400.00
0.00
0.00
0,00
25.00
35
8
15.00
6.00
0.00
43,20
6.00
0.00

15
0.00
0.00
49.600.00
0.00
2,00
3.300.00
25.00
35
8
12.50
3.75
3.30
24.80
0.00
0.00

35
0.50
15
0
0
22000
0
2
2300
25
35
8
17.50
5.25
2.30
11.00
0.00
0.00

15
8000
10000
32000
0
0
0
25
35
8
16.00
4.80
0.00
16.00
0.00
0.00

15
20000
10000
14000
1500

33.75

33.75

33.75

33.75

33.75

0,00

0.00

0.00

0.00

0.00

103.95

78.10

69 8

70.55

58.45

153.24

116.26

91.97

103.48

111.78

Lube and oil as % o f fuel (fpi %
Track and undercarriage
Track and undercarriage life (Thi h
Annual repair & maintenance (Rpi S
Annual operating supplies (Oci $
Annual tire consumption (ti no.
Tire replacement (tci $
Operator wages $/h
Wage benefit loading (WBLi %
Shift length (sli h
Fuel (F*fci $/h
Lube and oil ((fp/100*(F*fcii $/h
Tires ((tc*ti/hi $/h
Repair and maintenance (Rp/hi $/h
Track and Undercarriage (Tc/Thi
Operating supplies (Oc/bt $/h
Wages and benefits
rw */'i4-w nt /lo o t tiu
Prorated overtime
(((1.5*W-W)*(sl-

Total operating costs (OP) $/h
T O T A L O W N E R S H IP AND

OPERATING COSTS (OW +OP) S/h

25
35
8
11.50
3.45
7.00
2
0.75

“ Y a rd e r c o s t in c lu d e s th e c o s t fo r a n o n -s la c k p u llin g c a rria g e .
* W a g e C o s tin g :

F e lle r is o n a d a y r a te o f $ 4 0 0 b a s e d o n a n 8 - h o u r w o r k d a y a n d th e b u c k e r is o n a n h o u r ly r a te

o f $25 per hour

122

Appendix 8 -T im e data for East Twin Felling
A vg.
tim e /e le m e n t

T im e /C y c le
fo/.

F e lle r

T im e /C y c te

T im e /C y c le

_________ ( m i n ) _________

(m in )

(m in )
T re a tm e n t

A vg.
tim e /e le m e n t

G ro u p S e le c tio n

C le a rc u t

(7 0 % re te n tio n )

G ro u n d -b a sed

C le a r c u t

A

A

A

A

C a b le
B

B

P ro d u c tiv e E le m e n ts :
M o v in g

0 .3 0 2

9 .6

0 .3 5 9

1 0 .0

0 .3 6 7

1 8 .6

B ru s h in g

0 .0 6 5

2 .1

0 .0 9 6

2 .7

0 .0 7 6

3 .8

C u ttin g

1 .1 9 2

3 8 .1

1 .1 7 5

32^

0 .7 9 9

4 0 .6

W e d g in g

0 .0 8 6

2 .7

0 .1 1 2

3 .1

0 .0 1 2

0 .6

B u c k in g

0 .0 2 1

0 .7

0 .0 1 5

0 .4

0 .0 0 0

0 .0

S h o v e llin g

0 .1 6 5

5 .3

0 .1 8 3

5 .1

0 .0 1 9

0 .9

R e c o n n a is s a n c e

0 .0 3 4

1.1

0 .0 4 3

1 .2

0 .0 1 8

0 .9

T o ta l P ro d u c tiv e T im e

1 .8 6 4

5 9 .6

1 .9 8 3

5 5 .4

1 .2 9 0

6 5 .5

R e s tin g

0 .5 7 0

1 8 .2

0 .5 1 0

1 4 .2

0 .4 0 3

2 0 .5

F u e llin g sa w

0 .1 0 2

3 .3

0 .1 2 3

3 .4

0 .0 7 9

4 .0

N o n P ro d u c tiv e E le m e n ts

F ilin g sa w

0 .0 5 4

1 .7

0 .0 1 9

0 .5

0 .0 8 8

4 .5

F ix in g sa w

0 .0 2 1

0 .7

0 .1 4 8

4 .1

0 .0 9 9

5 .0

0 .0 0 1

0 .0

0 .0 6 1

1 .7

0 .0 1 1

0 .6

H ik in g in b lo c k

0 .0 6 7

2 .1

0 .0 5 6

1 .6

0 .0 0 0

0 .0

C h o k in g tre e s

0 .0 4 3

1 .4

0 .3 0 2

8.4

0 .0 0 0

0 .0

W a itin g fo r s k id d e r

0 .0 3 9

1 .2

0 .1 4 0

3 .9

0 .0 0 0

0 .0

L unch

0 .3 6 8

1 1 .8

0.238

6.6

0 .0 0 0

0 .0

1 .2 6 5

4 0 .4

1 .5 9 6

4 4 .6

0 .6 8 1

3 4 .5

3 .1 3 0

1 0 0 .0

3 .5 7 9

1 0 0 .0

1 .9 7 0

1 0 0 .0

M o v in g e q u ip m e n t a n d
fu el

T o ta l N o n -P ro d u c tiv e
T im e

T o ta l C y c le T im e

G ro u p S e le c tio n

C le a rc u t

C le a rc u t

(7 0 % re te n tio n )

G ro u n d -b a se d

C a b le

A

A

B

V o lu m e / P M H (m ^ /h r)

3 9 .2 7

4 6 .6 0

6 8 .3 7

V o lu m e / S M H (m ^ /h r)

2 3 .3 7

2 5 .8 1

4 4 .7 6

F e llin g c o s t ($ /h r)

5 0 .0 0

5 0 .0 0

5 0 .0 0

1 rc d iiiic iii
F e lle r

F e llin g c o s t / P M H ($ /m ^ )

1 .2 7

1 .0 7

0 .7 3

F e llin g c o s t / S M H ($ /m ^ )

2 .1 4

1 .9 4

1 .1 2

123

Appendix 9 - Time Data for East Twin Skidding
A v g . tim e /e le m e n t
(m in )
T re a tm e n t

T im e /C y c le (% )

A v g . tim e /e le m e n t
(m in )

T im e /C y c le (% )

G ro u p S e le c tio n

C le a rc u t

(7 0 % re te n tio n )

G ro u n d -b a se d

P ro d u c tiv e C y c le E le m e n ts
T r a v e l e m p ty

3 .5 1

1 6 .4 3

2 .7 4

1 4 .8 1

W in c h lin e o u t

0 .9 0

4 .2 2

0 .6 9

3 .7 1

W in c h lin e in

0 .7 2

3 .3 7

0 .6 0

3 J4

R e p o s itio n in g

0 .1 2

0 .5 5

0 .0 7

0 .2 9

C h o k e #1

2 .8 6

1 3 .4 0

24 2

1 3 .0 8

C hoke #2

1 .6 2

7 .5 7

1 .4 6

7 .9 1

C h o k e #3

0 .7 0

3 .2 6

0 .5 9

3 .2 1

C hoke #4

0 .3 9

1 .8 3

0 .1 8

0 .9 5

C hoke #5

0 .0 8

0 .3 7

0 .0 0

0 .0 0

T o ta l c h o k in g tim e

5 .6 4

2 6 .4 2

4 .6 5

2 5 .1 5

T rav el L o ad ed

4 .3 8

2 0 .5 1

4 .2 9

2 3 .2 1

U n c h o k in g

1 .3 5

6 .3 4

1 .1 3

6 .0 8

D e lim b in g

0 .3 0

1 .4 1

1 .3 2

7 .1 4

R e c o n n a is s a n c e

0 .0 3

0 .1 4

0 .0 2

0 .1 1

T u r n in g o n la n d in g

1 .5 3

7 .1 6

0 .0 0

0 .0 0

T o ta l P ro d u c tiv e T im e

1 8 .4 7

8 6 .5 5

1 5 .5 0

8 3 .7 4

W a it fo r tra c to r s k id d e r

0 .3 1

1 .4 6

0 .2 0

1 .0 9

W a it fo r ta lle r

0 .1 4

0 .6 5

0 .0 0

0 .0 0

R e p a ir w in c h lin e

0 .3 3

1 .3 2

0 .5 0

2 .7 0

W a it fo r lo a d e r

0 .1 5

0 .6 8

0 .1 3

0 .7 1

P e rs o n a l d e la y

0 .0 5

0 .2 4

0 .1 4

0 .7 3

G e n e ra l re p a ir

0 .0 4

0 .1 9

0 .0 0

0 .0 0

C h o k e r re p a ir

0 .6 3

2 .9 7

0 .0 0

0 .0 0

R e c h o k in g tre e (s )

0 .1 4

0 .6 7

0 .0 0

0 .0 0

C le a rin g s k id tra il

0 .2 2

1 .0 3

0 .4 1

2 .2 4

T o ta l N o n -P ro d u c tiv e T im e

Z87

1 3 .4 5

3 .0 1

1 6 .2 6

T o ta l C y c le T im e

2 1 .3 4

1 0 0 .0 0

1 8 .5 0

1 6 .2 6

124

T re a tm e n t

G ro u p S e le c tio n

C le a rc u t

(7 0 % re te n tio n )

G ro u n d -b a s

2 3 8 .7 0

1 4 0 .8 0

8

5

T r e e s in c h o k e # 1 /c y c le (n o .)

2 .8 6

2 .4 3

T r e e s in c h o k e # 2 /c y c le (n o .)

1 .7 2

1 .1 1
0 .5 1

A v e ra g e d is ta n c e (m )

N u m b e r o f c h o k e rs a v a ila b le
C h o k in g a v e ra g e s

T r e e s in c h o k e # 3 /c y c le (n o .)

0 .8 9

T r e e s in c h o k e # 4 /c y c le ( n o .)

0 .3 2

0 .3 0

T r e e s in c h o k e # 5 /c y c le (n o .)

0 .0 7

0 .0 0

A v e ra g e p ie c e s /c y c le (n o .)

5 .8 6

4 .3 5

V o lu m e / P M H (m ^ /h r)

2122

2 5 .9 5

V o lu m e / S M H (m ^ /h r)

2 0 .0 9

2 1 .7 2

S k id d e r c o s t ($ /h r)

8 9 .7 4

8 9 .7 4

S k id d in g c o s t / P M H ($ /m ^ )

3 86

3 .5 0

S k id d in g c o s t / S M H ($ /m ^ )

4 .4 7

4 .1 3

125

Appendix 10 -Tim e Data for East Twin Yarding
A v g . tim e

A v g . tim e

/e le m e n t

T im e /C y c le

/e le m e n t

T im e /C y c le

(m in )

(% )

(m in )

(% )

P r o d u c tiv e C y c le E le m e n ts

N o n -p ro d u c tiv e E le m e n ts

O u th a u l

0 .7 4 0

7 .8 0

Y a rd e r s e ttin g c h a n g e tim e

1 .0 0 6

1 0 .6 8

H ookup

3 .1 3 0

3 3 .2 2

W arm a n d fu e l u p

0 .3 1 7

3 J6

H o okup #2

0 .1 3 0

1 .3 5

R e p la c in g c h o k e r

0 .1 8 7

1 .9 8

In h a u l

2 .2 4 0

2183

R e p a ir in g m a in lin e

0 .1 6 8

1 .7 8

U nhook

0 .8 4 0

889

T o ta l p ro d u c tiv e tim e

T o ta l c y c le tim e (m in )

C y c le s p e r h o u r (n o .)

7 .0 8 0

9 .4 2 0

7 5 .1 0

1 0 0 .0 0

G e n e ra l re p a irs

0 .1 1 6

1 .2 3

A d ju s tin g g u y lin e s

0 .0 8 2

0 .8 7

W a it fo r lo a d e r

0 .0 8 1

0 .8 6

R e p a irin g h a u lb a c k d ru m

0 .0 7 7

0 .8 2

B ro k e n s tra w lin e

0 .0 7 0

0 .7 4

A d ju s tin g h a u lb a c k b ra k e

0 .0 5 2

0 .5 5
0 .5 3

T a n g le d lin e s

0 .0 5 0

R e c h o k in g lo g

0 .0 4 7

0 .5

U n ta n g lin g lo g s

0 .0 3 2

0 .3 4

W a it fo r c h o k e rm a n

0 .0 3 0

0 .3 2

C o m m u n ic a tio n

0 .0 2 4

0 .2 6

R e p a irin g c a rria g e

0 .0 2 1

0 .2 2

P e rs o n a l d e la y

0 .0 2 0

0 .2 1

C r o s s e d lin e s

0 .0 0 5

0 .0 5

W a it fo r b u c k e r

0 .0 0 4

0 .0 4

W a it fo r c h a s e r

0 .0 0 1

0 .0 1

T o ta l n o n -p r o d u c tiv e tim e

2 .3 8 8

2 4 .9 0

6 .3 7

A v g . p ie c e s /c y c le (n o .)

2 .5 9

A v g . y a rd in g d is ta n c e (m )

1 5 5 .9 8

N o . o f tim e d c y c le s

297

T o ta l h a r v e s te d v o lu m e (m ^ )

2 9 8 7 .9

T o ta l tre e s (n o .)

2031

V o lu m e p e r tr e e (m ^ )

1 .4 7

V o lu m e /P M H (m ^ /h r)

3 2 .4 9

V o lu m e /S M H

2 4 .2 5

Y a r d e r c o s t (S /h r)

1 8 7 .5 8

Y a r d in g c o s t/ P M H ($ /m ^ )

5 .7 7

Y a r d in g c o s t/ S M H ($ /m ^ )

7 .7 4

126

Appendix 11 - Detailed East Twin Landing Activity Sampling
Element “
Harvesting
system
Silvicultural
treatment

Ground-based
Group selection
Delay

Skidder/yarder

Loader

Bucker

%of
Time
%of
Time
Time
%of
(min/hr) time (min/hr) time (min/hr) time

Delayed on
Landing
Off landing
Productive
Working
Delayed on
landing
Delay
Waiting for
logs
Productive Working
Delayed
from
working
Waiting for
Delay
logs
Refuelling
and/or filing
Productive

Working

Cable

Clearcut

Clearcut

0.00

0.00

0.00

0.00

0.00

0.00

55.10
4.90

91.84
8.16

56.00
4.00

93.33
6.67

46.50
13.50

77.50
22.50

2.76

4.59

2J3

3.89

11.25

18.75

29.39

48.98

3033

50.56

3.00

5.00

27.86

46.43

27.33

45.56

45.75

76.25

3.37

5.61

3.00

5.00

7.13

11.88

23.57

39.29

24.67

41.11

5.63

938

4.59

7.65

4.33

7.22

4.50

7.50

47.45

28.00

46.67

42.75

71.25

28.47

® D e n o te s i f th e e q u ip m e n t o r p e r s o n n e l a re d e la y e d b y

a n o th e r o p e ra tio n o n th e la n d in g , w o rk in g o n th e

la n d in g , n o t o n th e la n d in g , a n d w a itin g f o r tim b e r (n o w o r k a v a ila b le ) o n th e la n d in g .
*’ S a w r e f u e l l i n g a n d / o r f i l i n g o c c u r s o f f o f t h e l a n d i n g b u t l i m i t s b u c k e r s t o t a l p r o d u c t i v e t i m e .

127

Appendix 12 -Tim e data for Minnow Mechanized Felling

Silvicultural treatment

A v g . tim e

T im e /

A v g . tim e

T im e /

A v g . tim e

T im e /

/ e le m e n t

C y c le (% )

/ e le m e n t

C y c le (% )

/ e le m e n t

C y c le (% )

(m in )

(m in )

Group selection

Group retention

(m in )

Clearcut

Productive Elements;
M o v in g fro m tre e to tre e

0 .3 4

2 4 .3 7

0 .3 1

2 2 .9 7

0 .3 7

2 9 .0 9

B ru s h in g

0 .1 2

8 .4 3

0 .1 0

7 .4 8

0 .0 7

5 .7 0

C u ttin g

0 .0 4

3 .0 8

0 .1 0

7 .4 7

0 .0 5

3 .9 5

P u s h in g

0 .0 1

0 .9 0

0 .0 2

1 .2 8

0 .0 3

2 .0 3

B u n c h in g

0 .2 6

1 8 .3 1

0 .2 1

1 5 .3 1

0 .2 4

1 8 .6 6

R e p o s itio n in g

0 .0 1

0 .8 5

0 .1 1

8 .4 3

0 .0 9

6 .9 7

R e c o n n a is s a n c e

0 .0 3

2 .0 6

0 .0 2

1 .3 3

0 .0 1

1 .1 3

0 .8 2

5T99

0 .8 7

0 .8 7

6 7 .5 4

T o ta l P ro d u c tiv e T im e

6 4 .2 7

Non Productive Elements
W a lk in g

0 .1 5

1 0 .4 2

0 .0 4

3 .1 6

0 .0 7

5 .3 9

R e s tin g

0 .0 7

5 .1 7

0 .0 6

4 .7 1

0 .0 5

4 .0 7

P e rso n a l

0 .0 4

0 .0 6

4 .4 9

0 .0 1

0 .6 8

W a it fo r s k id d e r

0 .0 0

0 .0 0

0 .0 3

2 .0 7

0 .0 0

0 .3 5

C o m m u n ic a tio n

0 .0 7

4 .6 9

0 .0 5

3 .9 9

0 .1 1

8 .6 0

C le a rin g tra il

0 .0 0

0 .1 4

0 .0 0

0 .0 0

0 .0 0

0 .0 4
0 .0 0

S tu c k

0 .1 2

8 .3 7

0 .0 0

0 .0 0

0 .0 0

R e p a ir

0 .0 2

1 .5 9

0 .0 9

6 .9 3

0 .0 4

3 .2 0

L unch

0 .0 6

4 .1 7

0 .0 6

4 .1 9

0 .0 5

4 .1 6

W a rm in g u p

0 .0 4

3 .1 0

0 .0 4

3 .0 9

0 .0 4

2 .9 9

F u e llin g u p

0 .0 4

3 .1 0

0 .0 4

3 .0 9

0 .0 4

2 .9 9

T o ta l N o n -P ro d u c tiv e T im e

0 .5 9

4 2 .0 1

0 .4 8

3 5 .7 3

0 .4 2

3 2 .4 6

Total Cycle Time

1 .4 1

1 0 0 .0 0

1 .3 5

1 0 0 .0 0

1 .2 9

1 0 0 .0 0

Group selection

Group retention

Clearcut

A v e ra g e s lo p e (% )

2 1 .0 4

1 2 .1 7

2 8 .4 9

T o ta l tre e s m u ltic u t (% )

3 .2 4

1 6 .8 1

1 0 .1 4

Silvicultural treatment

V o lu m e / tr e e (m ^ )

1 .0 5

1 .0 7

0 .9 1

V o lu m e / P M H (m ^ /h r)

7 7 .3 4

7 4 .3 6

6296

V o lu m e / S M H (m ^ /h r)

4 4 .8 5

4 7 .7 9

4 2 .5 2

F e llin g c o s t ($ /h r)

1 5 3 .2 4

1 5 3 .2 4

1 5 3 .2 4

F e llin g c o s t / P M H ($ /m ^ )

1 .9 8

2 .0 6

2 .4 3

F e llin g c o s t / S M H ($ /m ^ )

3 .4 2

3 .2 1

3 .6 0

128

Appendix 13 - Time Data for Minnow Skidding

S ilv ic u ltu ra l tr e a tm e n t

A v g . tim e /

T im e /

A v g . tim e

T im e /

A v g . tim e

T im e /

e le m e n t

C y c le

/ e le m e n t

C y c le

/ e le m e n t

C y c le (% )

(m in )

(% )

(m in )

(% )

(m in )

G r o u p s e le c tio n

G ro u p re te n tio n

C le a rc u t

P ro d u c tiv e E le m e n ts :
T r a v e l e m p ty

3 .1 8

2 4 .2 0

2 .3 0

2159

4 .6 4

L o a d in g

0 .1 9

1 .4 3

0 .3 4

3 .7 4

0 .2 1

1 .4 8

A c c u m u la tin g

0 .9 8

7 .4 9

0 .7 0

7 .7 7

1 .1 4

7 .8 8

R e p o s itio n in g

0 .0 0

0 .0 0

0 .0 0

0 .0 4

0 .0 0

0 .0 1

T r a v e l lo a d e d

3 .0 6

2125

2 .5 0

2 7 .7 6

3 .7 8

2 6 .1 6

3 2 .1 0

U n lo a d in g

0 .0 5

0 .3 6

0 .1 0

1 .1 1

0 .0 4

0 .3 0

S e p a ra tin g s k id d e d tre e s

0 .6 8

5 .1 5

0 .4 0

4 .4 1

0 .7 0

4 .8 3

D e lim b in g

0 .4 4

3 .3 5

0 .9 0

1 0 .0 0

0 .5 1

3 .5 6

R e c o n n a is s a n c e

0 .0 6

0 .4 5

0 .0 4

0 .4 6

0 .0 3

0 .2 3

6 5 .6 7

7 .2 7

8 0 .8 9

1 1 .0 7

7 6 .5 6

4 .3 6

T o ta l P ro d u c tiv e T im e

N o n P r o d u c tiv e E le m e n ts
C le a r in g tra il

0 .0 0

0 .0 0

0 .1 5

1 .6 8

0 .6 3

T r a v e lin g b e tw e e n la n d in g s

0 .0 4

0 .3 0

0 .0 1

0 .1 6

0 .1 6

1 .1 1

C o m m u n ic a tio n s

0 .4 7

3 .6 1

0 .0 8

0 .9 1

0 .4 5

3 .0 8

P e rso n a l

0 .1 0

0 .7 6

0 .0 1

0 .1 4

0 .0 5

0 .3 5

W a it o n la n d in g

0 .0 0

0 .0 0

0 .4 0

4 .4 9

0 .3 6

2 .4 8

W a it fo r fe llin g

0 .0 0

0 .0 0

0 .0 1

0 .1 4

0 .0 1

0 .0 9

W a it fo r h o e c h u c k in g

0 .1 4

1 .0 4

0 .0 0

0 .0 0

0 .1 9

1 .2 9

W a it fo r c at

0 .0 0

0 .0 0

0 .0 4

0 .4 4

0 .0 0

0 .0 0

M a in te n a n c e

0 .1 9

1 .4 5

0 .0 5

0 .5 6

0 .2 0

1 .3 5

M e c h a n ic a l

1 .5 6

1 1 .8 5

0 .0 0

0 .0 0

0 .1 1

0 .7 5

F o rw a rd in g p ro c e s s e d w o o d

0 .3 6

2 .7 7

0 .0 6

0 .6 1

023

1 .5 8

C le a r in g la n d in g

0 .0 8

0 .6 2

0 .1 9

2 .0 9

0 .0 8

0 .5 9

S k id d e r o r tu rn s tu c k

0 .0 0

0 .0 0

0 .0 0

0 .0 0

0 .0 5

0 .3 2

W a rm in g u p

0 .4 8

3 .6 7

0 .4 1

4 .5 2

0 .4 6

3 .1 6

F u e llin g u p

0 .4 2

3 .1 8

0 .3 0

135

0 .4 2

2^2

T o ta l N o n -P ro d u c tiv e T im e

4 .5 1

3 4 .3 3

1 .7 2

1 9 .1 1

3 .3 9

2 3 .4 4

T o ta l C y c le T im e

1 3 .1 4

1 0 0 .0 0

8 .9 9

1 0 0 .0 0

1 4 .4 7

1 0 0 .0 0

129

Silvicultural treatment

Group selection

Group retention

A v e ra g e p ie c e s /c y c le (n o .)

4 .8 3

4 .6 0

Clearcut
5 .6 3

A v e ra g e s lo p e (% )

1 5 .4 9

1 3 .3 5

2 7 .1 8

A v e ra g e tu rn le n g th (m )

2 6 .1 7

2823

2 5 .0 0

A v e ra g e d is ta n c e lo a d e d (m )

2 4 6 .7 5

1 3 3 .8 9

2 7 3 .7 0

A v e ra g e d is ta n c e e m p ty (m )

2 4 6 .7 5

1 3 3 .8 9

2 8 9 .1 6

T u rn s h o e c h u c k e d (% )

2 0 .1 8

0

2 5 .5 8

V o lu m e / tr e e (m ^ )

1 .0 5

1 .0 7

0 .9 1

V o lu m e / tu r n (m ^ )

5 .0 9

4 .9 3 7 6 2 1 8

5 .1 3

V o lu m e / P M H (m ^ /h r)

3 5 .4 0

4 0 .7 3

2 7 .8 1

V o lu m e / S M H (m ^ /h r)

2325

32.95

2 1 .2 9

S k id d e r c o s t ($ /h r)

1 1 6 .2 6

1 1 6 .2 6

1 1 6 .2 6

S k id d in g c o s t / P M H ($ /m ^ )

328

2 .8 5

4 .1 8

S k id d in g c o s t / S M H ($ /m ^ )

5 .0 0

323

5 .4 6

130

Appendix 14 -Detailed Minnow Landing Activity Sampling
Time
Element ® (min/hr)
Harvesting system
Silvicultural treatment
Delay Delayed on
Landing
Skidder/yarder
Off landing
Productive
Working
Delayed on
landing
Delay
Loader
Waiting for
logs
Productive Working
Delayed
from
working
Delay Waiting for
Bucker
logs
Refuelling
and/or
filing
Productive Working

%of
Time
%of
time (min/hr) time
Ground-based
Group selection
Clearcut

Time
%of
(min/hr) time
Cable
Clearcut

2.31

3.85

2.62

4.36

5.44

9.06

46.62
11.08

77.69
18.46

40.00
17.38

66.67
28.97

44.23
10.33

73.72
17.22

16.15

2642

4.92

8.21

12.33

20.54

2.00

333

7.69

12.82

3.08

5.14

41.85

69.74

47.38

78.97

44.59

74.32

12.77

21.28

5.54

9.23

4.89

8.16

12.31

20.51

7.85

13.08

19.94

33.23

2.77

4.62

6.15

10.26

3.81

6.34

32.15

5339

40.46

67.44

31.36

52.27

” D e n o t e s i f t h e e q u i p m e n t o r p e r s o n n e l a r e a e i a y e a t>y a n o t n e r o p e r a t i o n o n t n e

la n d in g ,

la n d in g , n o t o n th e la n d in g , a n d w a itin g f o r tim b e r (n o w o r k a v a ila b le ) o n th e la n d in g .
S a w r e f u e llin g a n d /o r filin g o c c u r s o f f o f th e la n d in g b u t lim its b u c k e r s to ta l p r o d u c tiv e tim e .

131