RESEARCH EXTENSION NOTE
NO. 5 – Oct 2009

Propagation and Fungal Inoculation of Black
Huckleberry and Velvet-Leaf Blueberry: How
Can These Species be Used in Ecological
Reclamation?

By
Irene M. McKechnie, Philip J. Burton & Hugues
B. Massicotte

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

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The Natural Resources and Environmental Studies Institute Research
Extension Notes (REN) are peer-reviewed publications of the research
findings of NRES Institute members and of graduate students in the NRES
Graduate Program. NRESI Research Extension Notes are intended to
provide an outlet through which Institute Members can make their research
findings available to a non-technical audience.
Irene McKechnie is a recent M.Sc. NRES (Biology) graduate from UNBC.
Phil Burton is an Adjunct Associate Professor in the Ecosystem Science and
Management program at UNBC and Manager of Northern Projects for the Pacific
Forestry Centre, Canadian Forest Service.
Hugues Massicotte is a Professor in the Ecosystem Science and Management program at
UNBC.

The correct citation for this paper is:
McKechnie, I.M., Burton, P.J. and Massicotte, H.B. 2009. Propagation and fungal
inoculation of black huckleberry and velvet-leaf blueberry: How can these species
be used in ecological reclamation? Natural Resources and Environmental Studies
Institute Research Extension Note No. 5, University of Northern British Columbia,
Prince George, B.C., Canada.
This paper can be downloaded without charge from
http://www.unbc.ca/nres/research_extension_notes.html

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NRESi Research Extension Note No. 5
Oct 2009

The Natural Resources and Environmental Studies Institute (NRES Institute) is a
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URL: www.unbc.ca/nres

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

iv

CONTENTS
Abstract ............................................................................................................................... 2
Introduction ......................................................................................................................... 3
Methods............................................................................................................................... 4
Results ................................................................................................................................. 6
Discussion and Recommendations ..................................................................................... 7
Conclusions ....................................................................................................................... 10
References ......................................................................................................................... 11
Further Readings or Resources ................................................................................... 11
Acknowledgements ........................................................................................................... 12

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

1

Abstract
There is great demand for the inclusion of
berry-producing plants, such as wild
blueberries or huckleberries (Vaccinium
species), in forest restoration and postindustrial reclamation efforts, due to their
value to wildlife and traditional users of the
land. However, the biology and propagation
requirements of northern Vaccinium species
and their potential for use in reclamation,
ecological restoration, and horticulture are
largely unexplored. Propagation trials of
black huckleberry (V. membranaceum) and
velvet-leaf blueberry (V. myrtilloides) using
seeds, hardwood cuttings, and rhizome
cuttings were carried out to determine
propagation protocols. Outdoor trials tested
the influences of mycorrhizal inoculation

2

and soil amendment on seedling survival.
Seeds and rhizome cuttings were found to be
the most effective propagation techniques
for Vaccinium. Soil amendment increased
outdoor seedling survival; however, none of
the
seedlings
showed
mycorrhizal
colonization, regardless of inoculation
treatment. These Vaccinium species are
dominant components of climax sub-boreal
forests, well adapted to recovery after fire;
however it is difficult for them to establish
rapidly on degraded soils, making soil
amendments important to their use in
ecological restoration. Growers must have
patience when growing northern Vaccinium
plants, but successful establishment is
possible with adequate care and planning.

NRESi Research Extension Note No. 5
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Introduction
Ericaceous plants such as the many species
of blueberry, huckleberry, and cranberry
occur worldwide, often growing under
harsh, nutrient-poor conditions. There is
great demand for the inclusion of berryproducing plants, such as black huckleberry
(Vaccinium membranaceum Douglas ex
Torr.) and velvet-leaf blueberry (V.
myrtilloides Michx.), in forest restoration
and post-industrial reclamation efforts, due
to their value to wildlife and traditional
users of the land (Minore 1972). However,
the biology and propagation requirements of
northwestern Vaccinium species and their
potential for use in reclamation, restoration,
and horticulture remain largely unexplored.
Propagation by seeds is one of the oldest and
most commonly used methods of shrub
propagation. This method allows for the
maintenance of genetic variability, and
hence the potential for future genetic
adaptations in lines of plant material (Rose
et al. 1998). Seeds can be collected from
many sources including seed orchards,
nursery stock, and native populations.
Vaccinium berries are collected in late
summer or early fall. Both number and
quality of berries produced by the plants can
vary greatly year to year depending upon
weather conditions during the growing
season (Small and Catling 2005). Studies
have suggested that Vaccinium seeds can be
stored for up to 13 years without losing
viability (Dirr and Heuser 1987). Vaccinium
seedlings, however, grow very slowly, and
this is a main reason that this technique is
not often used for this genus.
Propagation from vegetative cuttings is one
of the most economical techniques for shrub
propagation.
The resulting plants are
genetic clones of the parent plant and will
maintain all of its characteristics, but with
none of the incompatibility issues noted

when using grafting or budding techniques
(Dirr and Heuser 1987). When propagating
plants using cuttings, both stem cuttings and
root cuttings can be used. Limited success
has been reported using stem cuttings for
black
huckleberry,
however,
other
Vaccinium species have been reported to
root very successfully using stem cuttings
(Kender 1967). Several Vaccinium species
have been found to sprout from rhizome
cuttings taken while the plant is dormant
(Rose et al. 1998). The use of both stem and
rhizome cuttings in the propagation of
Vaccinium plants is an area that needs
further research.
Ericoid mycorrhizal relationships benefit
ericaceous plants, including Vaccinium spp.,
by allowing them to access nutrients that
would otherwise be unavailable (Smith and
Read 2008).
The mycorrhizal fungi
involved in these relationships appear to be
ubiquitous in natural environments, but they
are usually absent from potting mixes used
in greenhouses. This is most likely because
they can be killed by the water, fertilizers,
pesticides, and fungicides used in most
horticultural systems (Acree and Appleton
2000). Commercial inoculants are available
for some mycorrhizal fungi; however, they
are mostly developed for the more common
arbuscular mycorrhizal species.
The
inoculation of several cultivated Vaccinium
species with laboratory cultures of ericoid
mycorrhizal fungi has been shown to
increase fruit yield (Powell and Bates 1981)
and plant dry weight (Scagel 2005);
however, the influences of ericoid
mycorrhizal inoculation on the growth and
survival of Vaccinium species native to
western North America has not yet been
examined.
To address some of the gaps in native
Vaccinium propagation knowledge, the

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

3

research reported here consisted of testing
and optimizing the propagation and culture
of black huckleberry and velvet-leaf
blueberry using seeds, hardwood cuttings
(stem cuttings taken over the winter season),
and rhizome cuttings. The latter half of this
study was designed to look at factors
influencing the performance of Vaccinium
seedlings when they are moved from
greenhouse to outdoor conditions, such as
would occur if these species were used for
reclamation purposes. Field trials were set
up to determine the influence of mycorrhizal
inoculation and soil amendments on the
survival and growth of black huckleberry
and velvet-leaf blueberry seedlings.

Methods
Initial propagation trials for V.
membranaceum and V. myrtilloides were
carried out using seeds, hardwood cuttings,
and rhizome cuttings. In 2006, 2007, and
2008, seeds were extracted from multiple
provenances of locally collected berries and
surface sown on a 50:50 (by volume) peat:
sand growing medium. Growing trays were
kept under greenhouse conditions with a
21°/10°C day/night temperature and 15 hr
photoperiod. Germination numbers were
counted weekly after initial seedling
emergence for a period of 9 weeks in 2006,
13 weeks in 2007, and 14 weeks in 2008.
Hardwood cuttings were collected from

Figure 1. Outdoor planting sites. a) One field site showing amended and control plots.
b) Unamended plot showing placement of individual seedlings. c) Black huckleberry
seedling in unamended plot. d) Velvet-leaf blueberry seedling in amended plot.

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NRESi Research Extension Note No. 5
Oct 2009

local plants in early February 2007. The
bottom third of each cutting was submerged
in an indole-3-butyric acid (IBA) solution, a
synthetic growth hormone, and were planted
in either rockwool or a 50:50 peat: perlite
growing medium. Each treatment contained
60 cuttings. Growing trays were kept under
the same greenhouse conditions as above
with natural light conditions. Root
production by the cuttings was evaluated 62
days after the cuttings were planted.
Rhizome cuttings were collected from local
plants in October 2008. The cuttings were
planted in either vermiculite or a 50:50 peat:
perlite growing medium. Growing trays
were kept under the above greenhouse
conditions until a final evaluation of shoot
sprouting was conducted 65 days after

planting.
For the outdoor field trials, seeds were
collected
from
north-central
British
Columbia during the 2007 growing season.
These seeds were sown and kept under
greenhouse conditions with a 21°/10°C
day/night temperature and 15 hour
photoperiod. A sub-sample of 500 seeds per
species was monitored for germination. Six
months after sowing (when in the 4-10 leaf
stage), seedlings were inoculated, by
pipetting fungal solutions on to the soil
surface, with ericoid mycorrhizal fungi:
either Rhizoscyphus ericae (D.J. Read) W.Y.
Zhuang & Korf, Oidiodendron maius
Barron, or Meliniomyces sp. in a potato
dextrose agar (PDA) solution; control
seedlings were inoculated with only the

Figure 2. Vaccinium seeds and seedlings. a) Germinating velvet-leaf blueberry
seeds (2008). b) Black huckleberry seedlings 100 days from sowing (2008). c) Black
huckleberry seedlings 121 days from sowing (2007). d) Velvet-leaf blueberry
seedlings 148 days from sowing (2007).

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

5

sterile PDA solution. Approximately one
month after inoculation, 1440 seedlings
were transplanted to three field sites on the
University of Northern British Columbia
(UNBC) campus in Prince George, B.C.
Sixty seedlings were planted into each of
eight 1.4m x 1.4m plots that received
randomly assigned species, soil amendment,
and inoculation treatments at each of the
three sites (Figure 1). Half of the plots in
each site were amended with the equivalent
of a 10 cm depth of local forest floor
material (litter, fermentation, and humus
layers, including some rotting wood), while
the other half were left unamended.
Survival, dry biomass, and mycorrhizal
colonization status were assessed at the end
of the growing season (110 days). A
detailed discussion of the analytical methods
used for all of the trials discussed in this
note can be found in McKechnie (2009).

reached the 4-6 leaf stage, they began to
show morphological differences between
species (Figure 2). Germination levels for
black huckleberry and velvet-leaf blueberry
differed significantly over the three years of
observation (p=3.48 x 10-8). In 2006, 2007,
and 2008, overall germination levels for
black huckleberry seeds were 26.0 ± 4.9%
(mean ± standard error of the mean), 4.70 ±
1.29%, and 66.0 ± 4.24%, respectively. The
overall germination levels for velvet-leaf
blueberry seeds were 14.7 ± 4.9%, 13.0 ±
1.68%, and 28.5 ± 5.48%, over the same
three years (Figure 3).

Results

The sprouting of rhizome cuttings of black
huckleberry and velvet-leaf blueberry was
not influenced by the growing medium in
which they were planted (p=0.700).

None of the treatments tested impacted the
development of roots in hardwood cuttings
of black huckleberry and velvet-leaf
blueberry (p=0.079). Both species had a
very low success level of 2.5%, the
equivalent of 6 out of 240 cuttings surviving
(Figure 4, 5a-b).

Initially, black huckleberry and velvet-leaf
blueberry seedlings were indistinguishable
from one another. When the seedlings

Germination capacity (%)

80

a

70
60
50
40

2006

b

bc

2008

30

b

20
10

2007

b

bd

0
black huckleberry

velvet-leaf blueberry
Species

Figure 3. Total germination capacity (%) of black huckleberry and velvet-leaf
blueberry seeds collected in 2006, 2007, and 2008. Error bars represent ± one
standard error. Columns topped with the same lower case letter do not differ
significantly at p<0.05.

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NRESi Research Extension Note No. 5
Oct 2009

100

a

90

Survival (%)

80

a

70
60

hardwood cuttings

50

rhizome cuttings

40
30
20
10

b

b

0
black huckleberry

velvet-leaf blueberry
Species

Figure 4. Total survival levels (%) of black huckleberry and velvet-leaf blueberry
hardwood and rhizome cuttings. Error bars represent ± one standard error. Columns
topped with the same lower case letter do not differ significantly at p<0.05.

Overall, black huckleberry rhizome cuttings
sprouted at a rate of 70% and velvet-leaf
blueberry rhizome cuttings sprouted at a rate
of 85%, across all treatments (Figure 4, 5cd).
Black huckleberry and velvet-leaf blueberry
seedlings planted into field plots that had
been amended with forest floor material had
higher survival levels than those planted into
unamended field plots (Figure 6). In the
amended plots, black huckleberry seedlings
had survival levels of 8.33 ± 3.86% and
velvet-leaf blueberry seedlings had survival

levels of 28.33 ± 4.58%. In the unamended
plots, black huckleberry seedlings had
survival levels of 4.17 ± 1.93% and velvetleaf blueberry seedlings had survival levels
of 15.93 ± 3.79%. None of the fungal
inoculation treatments had any influence on
the survival levels of the seedlings. When
root samples were checked for mycorrhizal
colonization, none were found to be
colonized.

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

7

Discussion and
Recommendations
The seed germination levels varied
significantly among the different growing
years.
As growing conditions in the
greenhouses did not vary among years, the
significant differences in germination levels
between the years can be attributed to
natural variability in the seed lots. Given
the germination levels reported earlier, we
would recommend that growers over-sow
black huckleberry seeds at a minimum ratio
of 2:1 and velvet-leaf blueberry seeds at a
minimum ratio of 3:1 to adequately produce
the number of seedlings desired. Given our
personal observations over three growing

seasons, seed should be surface sown on a
peat/sand medium, ideally with a pH level
between 4.0 and 5.5. Seed trays should be
kept with a 21°C/10°C day/night
temperature regime and 12-15 hour of
light/day. Covering the seed trays with clear
plastic domes will decrease the amount of
watering required. With adequate watering,
and the occasional application of 20-20-20
N-P-K fertilizer, the seedlings should
require very little maintenance until they are
large enough to be transplanted into larger
growing containers. Vaccinium seedlings
grow slowly, and should ideally be left in
the greenhouse for 2-3 years prior to being
transplanted outdoors. During this time
period, the seedlings should be transplanted

Figure 5. Hardwood cuttings and rhizome cuttings. a) Velvet-leaf blueberry
hardwood cutting showing one root 62 days after planting. b) Black huckleberry
hardwood cutting growing in rockwool 50 days after planting. c) Velvet-leaf blueberry
rhizome cutting 153 days after planting. d) Black huckleberry rhizome cutting 153 days
after planting.

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NRESi Research Extension Note No. 5
Oct 2009

35

a

30
Survival (%)

25

ab

20
15
10

amended
unamended

bc
bc

5
0
black huckleberry

velvet-leaf blueberry
Species

Figure 6. Total survival levels (%), after 110 days, of black huckleberry and velvetleaf blueberry seedlings planted in amended and unamended plots. Error bars
represent ± one standard error. Columns topped with the same lower case letter do
not differ significantly at p<0.05.

into larger growing containers, as necessary,
to promote the growth of the root system.
Rhizome cuttings are an especially attractive
method of propagation where outplanting
material is desired in a short period of time,
and when plant salvage opportunities arise.
Rhizome cuttings from northern Vaccinium
species should be collected with care to
avoid damaging the parent plant (unless
conducted as a salvage operation prior to
habitat destruction), while also ensuring that
the correct species of rhizome is being
collected. Rhizomes can be collected at any
time during the fall and winter months,
when the plant is dormant (Dirr and Heuser
1987). When bringing rhizomes into the
greenhouse, it is important to either plant
them immediately or store them in an
environment where they will not dry out,
mold, or start to sprout on their own. Cold
storage at 4°C is usually sufficient for
meeting these requirements.
Rhizome
cuttings of at least 10 cm, or containing 2-3
nodes, should be planted into a peat/perlite
medium or vermiculite.
When using

vermiculite, care must be taken to ensure the
cuttings do not dry out, as this will happen
rapidly. If kept in a 21°C/10°C day/night
temperature regime and 12-15 hour of
light/day, the rhizome cuttings should sprout
in 1-2 months. By a visual assessment,
these cuttings grow more quickly than
seedlings and can be expected to be ready to
transplant outdoors after 6-12 months.
Another alternative may be to plant
unsprouted rhizome segments directly into
new outdoor locations, although the efficacy
of this method has not been tested. Given
the poor success of the hardwood cuttings,
the sheer number of cuttings that would
have to be planted in order to result in a
handful of viable plants makes this method
of propagation completely impractical at this
time.
Mycorrhizal
inoculation
of
black
huckleberry and velvet-leaf blueberry
seedlings under one year old does not appear
to be effective in producing mycorrhizal
colonization. It is interesting to note that all
of the rhizome cuttings were found to be

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

9

colonized by ericoid fungi, despite not being
inoculated in the greenhouse.
Further
research is required to determine the age at
which these seedlings begin to form
mycorrhizal associations and if the standard
protocols used to grow fungi are adequate.
Ideally, seedlings should be inoculated, with
resulting colonization, before they are
planted outside in order to take advantage of
the benefits derived from ericoid
mycorrhizas.
To the best of our knowledge, there are no
existing published guidelines for the growth
and transitioning of V. membranaceum or V.
myrtilloides seedlings from indoor to
outdoor growing conditions. Given the
results of this study, it is recommended that
if Vaccinium seedlings are to be taken from
greenhouse conditions to outdoor areas, they
should be at least two years old. Monitoring
growth rates of seedlings over a longer
period of time than was done in this study
would allow a determination of the age
when seedling growth rate begins to
decrease. This time period might indicate an
age where seedlings are less vulnerable to
external conditions and would be better able
to survive outdoors. Seedlings should be
planted early in the growing season, but
after the risk of frost, possibly in mid-May
for central British Columbia.
Outdoor
planting areas composed mainly of mineral
soil should be amended with local forest
floor materials to improve soil structure,
water retention, and nutrient availability.

10

Soils should be tested for pH prior to
planting and, if necessary, additional
amendments should be applied to reduce pH
to levels of less than 5 (Dirr and Heuser
1987)

Conclusions
Given the results of these studies, black
huckleberry and velvet-leaf blueberry plants
should be preferentially grown from seeds
when time is not a limiting factor, but labour
may be, and from rhizome cuttings when
time is a limiting factor, but labour is not.
While the influences of
mycorrhizal
inoculation remain unclear at this time, the
application of inoculant may benefit
growing plants, and certainly will not harm
them. Northern Vaccinium species are not
typically found as colonizers of severely
disturbed environments. Consequently, their
use in reclamation and ecological restoration
may be most suitable where conditions of
secondary succession (as characterized by a
more or less intact forest floor), prevail,
such as in clearcuts and under power lines.
Without soil amendments and careful
monitoring for moisture stress, it can be
quite difficult to establish these species in
areas dominated by bare mineral soil or
subsoil, such as pipeline excavations,
roadsides, or decommissioned roads and
landings.

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Oct 2009

References
Acree, G.E. and Appleton B.L. 2000. Mycorrhizal fungal inoculation of woody seed propagation
substrate. Combined Proceedings International Plant Propagators' Society 50:551-555.
Dirr, M.A. and Heuser, C.W. 1987. The reference manual of woody plant propagation. Varsity
Press, Inc., Athens, GA. 239p.
Kender, W.J. 1967. On the domestication of the lowbush blueberry. Fruit Varieties and
Horticultural Digest 21:74-76.
McKechnie, I. 2009. Propagation Methods and the Effectiveness of Fungal Inoculation on
Vaccinium Species Native to Central British Columbia [M.Sc. thesis]. University of
Northern British Columbia, Prince George, BC.
Minore, D. 1972. The wild huckleberries of Oregon and Washington: A dwindling resource. U.S.
Department of Agriculture Forest Service Research Paper-143. Pacific Northwest Forest
and Range Experiment Station, Portland, Oregon. 20p.
Powell, C.L. and Bates, P.M. 1981. Ericoid mycorrhizas stimulate fruit yield of blueberry.
HortScience 16:655-656.
Rose, R., Chachulksi, C.E.C. and Haase, D.L. 1998. Propagation of Pacific Northwest native
plants. Oregon State University Press, Corvallis, Oregon. 248p.
Scagel, C.F. 2005. Inoculation with ericoid mycorrhizal fungi alters fertilizer use of highbush
blueberry cultivars. HortScience 40:786-794.
Small, E. and Catling, P.M. 2005. Poorly known economic plants of Canada 45. Eastern
huckleberries (Gaylussacia spp.) and western huckleberries (Vaccinium spp.). Canadian
Botanical Association Bulletin 38:15-23.
Smith, S.E. and Read, D.J. 2008. Mycorrhizal Symbiosis. 3rd Ed. Academic Press, London.
787 p.

Further Readings or Resources:
Barney, D.L. 1999. Growing western huckleberries. University of Idaho, Moscow, Idaho. BUL
821. 22p.
Vander Kloet, S.P. 1988. The genus Vaccinium in North America. Pub 1828. Research Branch,
Agriculture Canada, Canadian Government Publication Centre, Ottawa. 201p.
Vander Kloet, S.P. and Hall, I.V. 1981. The biological flora of Canada 2. Vaccinium myrtilloides
Michx., Velvet-leaf blueberry. Canadian Field-Naturalist 95: 321-345.

McKechnie et al • Propagation and Fungal Inoculation of Vaccinium species

11

Acknowledgements
The authors thank J. Orlowsky and S. Storch (UNBC greenhouse) for technical growing
assistance and advice, M. Gorzelak for provision of fungal cultures, and C. Knudsen and S.
Patton (UNBC Maintenance) for assistance in preparing field sites. We are grateful to NSERC
for a Post-Graduate Scholarship to I. McKechnie and support to H.B. Massicotte in the form of a
Discovery Grant.

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