Structural Relationships Of Selected Tree Species at Several Mid-Latitude Deciduous Forest Sites in Virginia

Many computer models currently used by the U.S. Army require input of forest structural attributes. Knowledge of these attributes impacts cross-country mobility, cover and concealment, bivouac, etc. Access to direct ground measurement of these required parameters in denied areas is not always possible. This necessitates the capability to generate accurate estimates of selected forest features. Airborne imagery provides fairly high accuracy for such elements as tree crown diameter and tree height. Tree stem diameter (i.e., diameter at breast height (d.b.h.)) is an important parameter that cannot be measured directly by these sensors. This work involves the development of models to estimate d.b.h. from average crown diameter. More than 650 trees were measured in a series of 25 data collections at 11 sites in northern and north-central Virginia. The sites were dominated by uneven-aged deciduous trees, both forest grown and open grown. Models to predict d.b.h. from average crown diameter were generated and accuracy assessments are provided.