Stand development and growth responses of 1- and 3-year-old natural upland hardwoods to silvicultural treatments

Intense competition for growth resources between herbaceous and woody vegetation is considered a major constraint to the growth and development of newly regenerated forest stands. However, very few studies have explored silvicultural opportunities to manage these constraints. In this study, the effects of fertilization, density and vegetation control on rising 1- and 3-year-old upland mixed species NC Piedmont stands were monitored for 3 years following the imposition of treatments. Broadcast fertilization proved very beneficial in accelerating stem growth and promoting self-thinning at both sites. Weeding (non-arborescent vegetation) treatments without thinning had no effect on stem height. At both sites, substantial increases in tree size were noted for yellow-poplar and oaks when thinning and weeding treatments were combined. A significant fertilization effect on thinned plots was also noted for oaks. These results demonstrate that stem growth and stand development are constrained by the availability of site growth resources, and can be silviculturally managed to promote stand development.