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Techniques for reducing edge bias are discussed and a new approach, termed the linear expansion method, is presented. This method is applicable to a wide variety of plot shapes and sizes and is unbiased under very general assumptions about the forest tree spatial pattern. The accuracy and efficiency of the linear expansion method were compared with (i) no edge bias correction and (ii) corrections by plot image translation techniques for several forest stands and spatial patterns. Results indicated translation and the linear expansion method behaved equally well on square plots 0.08 ha in size. As the plot size diminished or its shape deviated from square, the linear expansion method provided greater accuracy and lower bias than translation techniques. The linear expansion method also provided useful accuracy on circular plots where translation was not feasible.

An individual tree based stand growth model was analyzed, via dynamic programming, for thinning and final harvest strategies leading to maximum physical yields. Optimal density yield tables, indicating maximum yields and corresponding strategies, were constructed from the solution of the dynamic programming networks. Maximum yields averaged 25 – 30% higher than comparable yields reported previously for periodically thinned red pine plantations.

A procedure is described for estimating timber volume from high-precision measurement of the cross-sectional area of a canopy profile on medium-scale vertical aerial photographs. Timber volume data were obtained from 75 data points in a study area containing several forest types, and canopy profile areas were measured with a stereoplotter at the corresponding points on the aerial photographs. Film density values were also measured along each profile using a scanning microdensitometer. Canopy profile area was found to be independent of the direction of the profile relative to the flight line of the photography. The relation between timber volume and profile area was found to be highly significant, semilogarithmic, and species dependent, with regression R2 values ranging from 0.67 to 0.79. The area under a curve obtained by plotting film density values is not sufficiently correlated with timber volume to be a significant independent variable, either alone or with profile area. However, film density information was found to be of significant value in correcting the profile areas for canopy microopenings too small to be measured with a stereoplotter. With the area of microopenings included as a separate independent variable, regression R2 values range from 0.82 to 0.88.