Growth response and cost comparisons for precommercial thinning methods of Appalachian oak stump sprout clumps

Abstract

Twelve-year-old stems of stump sprout origin were subjected to precommercial crop tree release treatments in an intermediate quality mixed Appalachian oak forest. Three chemicals (2,4-D, triclopyr, and kerosene) and two application methods (Hypo-hatchet® injection and stem spray) were compared with one another and with chainsaw felling in terms of crop and competitor growth response to thinning, productivity, and cost efficiency. After 5 yr, 2,4-D stem spray, triclopyr stem spray, and chainsaw treatments produced incremental diameter growth 28, 25, and 22% greater than unthinned controls, respectively. Triclopyr stem spray and chainsaw treatments were also most effective in controlling competitors. Stem spray and injection required 40 and 58% less time, respectively, and cost less than chainsaw felling. These results suggest that stem spray application of herbicides can be a cost effective alternative to chainsaw thinning for precommercial crop stem release of oak stump sprouts.