First-year regeneration in upland hardwoods after two levels of residue removal

Abstract

The effects of whole-tree removal versus conventional sawlog harvest on 1 st-year regeneration in an upland mixed hardwood site were compared, and sprouting dynamics of species and stump size classes were described. Average sprout production for stumps sampled was greater after conventional harvest: stumps produced taller, denser, and more abundant sprouts. Although sample sizes were small, maximum heights of stump sprouts of Quercusprinus L., Quercusvelutina Lam., and Acerrubrum L. were greater on the conventionally harvested area, and sprouts of Liriodendrontulipifera L. and Oxydendrumarboreum (L.) DC. averaged taller after residue removal. However, most species produced more seedlings after residue removal. Differences were related to greater site disturbance with whole-tree harvest. Number of sprouts and biomass per stump showed a binomial-shaped distribution in relation to stump diameter across both treatments, with a maximum at about 30 cm. Biomass of grape (Vitis spp.) was least following whole-tree removal, but this may be related to site quality or the small size of the study area. Regression estimates of sprout dry weight as a function of height were used to estimate sprout production. Conservative estimates of total stump sprout biomass, excluding foliage, 1year after whole-tree removal averaged 433 kg/ha and after conventional harvest averaged 679 kg/ha.