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Abstract
Two individual-tree growth simulators are used to predict the growth and mortality on a 30-year-old forest site and an 80-year-old forest site in eastern Kentucky. An empirical growth and yield model (NE-TWIGS, Hilt and Teck 1989) was developed to simulate short-term (< 50 year) forest growth from an industrial perspective. The gap model (ZELIG, Urban 1990) is based on the theory of growth processes and was designed to simulate long-term (100 years and greater) forest succession. Based on comparisons of species specific diameter distributions, biomass, and board-foot and cubic-foot volumes, NETWIGS performed better for the 80-year-old site than did ZELIG. Neither simulator provided acceptable predictions for the 30-year-old site.
Parent Publication
Citation
Yaussy, Daaniel A. 1999. Comparison of NE-TWIGS and ZELIG on actual growth of two sites in Kentucky. In: Stringer, Jeffrey W.; Loftis, David L., eds. 1999. Proceedings, 12th central hardwood forest conference; 1999 February 28-March 1-2; Lexington, KY. Gen. Tech. Rep. SRS-24. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 293 p
