Growth, yield, and financial return through six decades of various management approaches in a second-growth northern hardwood forest

Evaluation of long-term studies provides information about the sustainability of forest management on a time scale valuable to forest managers. A long-term silvicultural study at the Argonne Experimental Forest in northern Wisconsin has been continuously maintained for over six decades, providing an opportunity to test differences in growth and yield between three partial cutting methods: single-tree selection, crop tree release, and diameter-limit cutting. Over 65 years, results showed that single-tree selection with low residual stocking (14 m2 ha−1 basal area) performed best in regard to financial returns, growth, and yield, with high financial returns, greater levels of ingrowth, lower mortality, and greater residual percent volumes of high quality sawtimber. Diameter growth was maximized in low to moderate (17 m2 ha−1 residual basal area) residual stocking selection. The diameter-limit cut (18 cm dbh limiting diameter) was not successful in producing high-quality trees or consistent yield. After 50 years the crop tree release treatment did increase percent of high-quality harvested volumes, but to a lesser extent than the selection treatments. Selection treatments removing more basal area provided an overall better return on investment, providing potential incentive for modification to traditionally practiced single-tree selection to higher residual basal areas