RELATIVE EFFICIENCY OF SOME SPECIFIC PLOT-SIZES IN ESTIMATING TIMBER VOLUMES IN SOME SPECIFIC TIMBER TYPES

The following report illustrates the methods and results of making tests of the comparative efficiency of some plot-sizes in inventory work. The results of the tests showed that 1/10-acre plots are more efficient than 1/5-acre plots in inventories of 100-120-year-old Douglas fir stands; 1/10-acre plots are more efficient than 1/40-acre plots in inventories of 50-year-old Western hemlock stands; 1/5-acre plots are more efficient than 1/10-acre plots in inventories of mature uneven-aged Spruce-balsam stands; 1/4-acre plots are more efficient than either 1/20 or 1/2-acre plots in inventories of 50-year-old Douglas fir stands In addition to these tests in well-stocked stands, an inventory of a thinned stand of 50-year-old Douglas fir showed that 1/2-acre plots are more efficient than 1/4-acre plots.Admittedly the conclusions are limited to which is the most efficient of the two, or three, plot sizes tried in each type, and provides only an indication that an even larger, or a much smaller size, might have been more efficient than the ones tried.