aie nes

IV. RESULTS OF THE SURVEY i ¥olumes of Residue

Results of the study are shown in Table I and Table II. Table I shows the volume of solid residue per M ft.b.m. log scale produced by: (2) Sawmills cutting over 20 M ft.b.m. per 8-hour shift and (bo) Sawmills cutting 20 M ft.bem. or less per 8-hour shift. At all mills the cut was predominantly western white spruce but small amounts of Douglas fir, true fir, and lodgepole pine were sawn at some of the smaller mills.

Table II shows the volume of sawdust per M ft.b.m. log scale produced by the same mills, This volume of sawdust refers to the wood in solid form. When it is converted to sawdust it will assume a greater volume owing to the air spaces between each particle. Weighing and volume studics on sawdust indicate that 2.5 cubic fect of sawdust are produced from one cubic foot of solid wood.

It is outside the scope of this report to discuss the relative merits of the three types of headsaw. Each has its advantages and dis- advantages. However, studies in other arsas show a definite aving in log volume by the use of band headsaws. It should also be noted that mills cutting over 20 M ft.b.m. per day produce less solid residue.

This is probably due to the fact that the average log cut at these mills is larger than at the smaller mills (see Table III and Figure I).