Publication Date:
2020-08-19
Description:
Following timber harvests in bottomland mixed-oak (Quercus) stands, desirable oak advance regeneration can be overgrown by shade intolerant pioneer species. We investigated the effects of group selection opening size on composition of tree regeneration 19 years post-harvest in an oak dominated bottomland forest and compared our results with earlier findings to evaluate development trends. In response to six opening sizes (7 - 40 m radii) we evaluated regeneration density and dominance of four tree species groups: conifers, hard mast, shade intolerant and shade tolerant hardwoods. Our objective was to determine the optimum gap size for regenerating oaks and test the delayed oak dominance hypothesis, where oaks slowly gain dominance as pioneer species undergo self-thinning. Opening size influenced conifer regeneration but minimally affected hardwoods. Hard mast species density was less than either intolerant or tolerant species regardless of opening size. Future stem density trends suggest increasing intolerant species and constant mast and tolerant species. Modeled future height trends suggest increasing mast species dominance over intolerant pioneers after 30 years. Our results suggest that gap-based silviculture can be used to regenerate bottomland hardwood stands with desirable species including oaks; larger gaps favor conifers but there was no optimum size to enhance oak regeneration.
Print ISSN:
0045-5067
Electronic ISSN:
1208-6037
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
