Effects of precommercial thinning in naturally regenerated loblolly-shortleaf pine stands in the upper west gulf coastal plain: results after two growing seasonsThis article is part of a larger document. View the larger document here.
The benefits of precommercial thinning in naturally regenerated stands of southern pines have been well documented, but questions remain about how long precommercial thinning can be delayed and still be biologically and economically effective. In 2004, a precommercial thinning demonstration study was installed in naturally regenerated loblolly-shortleaf pine (Pinus taeda and P. echinata, respectively) stands that were 8, 14, and 19 years old. Treatments consisted of three levels of precommercial thinning with an unthinned control. Precommercial thinning promoted the growth of individual pines; dominant trees in the lowest retained densities annually grew 0.05 to 0.07 square feet in basal area regardless of stand age. However, stand-level growth was greatest for moderate densities because more trees occupied the site, offsetting the lower rates of tree growth. Tree mortality increased with increasing density and was a major element of stand dynamics. These results from our study provide foresters and landowners with a first look at the implications of delayed precommercial thinning with respect to individual tree and stand growth.