Potential impacts of increased management intensities on planted pine growth and yield and timber supply modeling in the South

Five management intensity classes were developed and used to estimate the p otential planted pine growth and yield levels to be applied in the 2000 Ran geland Renewable Resource Act (RPA) assessment. These planted pine yields a re compared to empirical pine yields, developed as a part of the Subregiona l Timber Supply model inputs and based on Forest Inventory Analysis (FIA) d ata. These comparisons indicate that planted pine yields are much greater t han empirical FIA data, e.g., up to 94 percent greater than current empiric al yields (2,361 ft.(3)/ac.) at the highest management intensity (4,587 ft. (3)/ac.) at age 25. Planted pine yields are also substantially higher than those used in the 1993 RPA assessment. If realized, such productivity incre ases could prevent potential timber shortages in the South. Financial analy ses indicate that intensified forest management offers attractive returns. For medium-quality sites, the calculated net present values are only $290/a c. for the basic empirical southern pine growth rates. They are $359/ac. fo r traditional planted pine management, $526/ac. with improved genetics, $58 1/ac. with fertilizers, $798/ac. with fertilizers and herbicides, and $939/ ac, with repeated applications of fertilizers and herbicides.