| Southern bottomland sites are among the most productive areas for producing high quality grade hardwood, yet the ability to estimate the quantity and quality of standing grade hardwood is almost non-existent. Measurements and observed log grades were recorded on standing trees to construct volume prediction models for individual trees. Several different modeling techniques were explored and compared during development. Developed equations predict merchantable sawtimber volume and volume by grade category in trees by species group. Two separate sets of equations were developed for each species group using either total height or merchantable height. Models were chosen based on significance of variables, index of fit, RMSE, bias, ease of use, and biological trends. The models developed to predict merchantable sawtimber and grade volumes were designed to be implemented in a larger hardwood growth and yield system. |
