Influence of Competition on the Density of the Federally Endangered Michaux's Sumac (Rhus michauxii) at Fort Pickett, Virginia

Abstract

Rhus michauxii (Michaux's sumac) is a federally endangered species native to the lower piedmont and upper coastal plain of the Southeastern United States. Fort Pickett, VA, has the largest known population and is unusual because the majority of the colonies are located in habitats maintained by frequent fire caused by military training. Our objectives were to investigate the relationship between woody competition and Michaux's sumac density. The strongest correlations were between woody competition and pistillate density. In the 2–5 m strata, the influence of woody density, total density, and DBH on pistillate Michaux's sumac density were significant (P < 0.05) and strongly correlated with r2 of 0.558, 0.488, and 0.511, respectively. Based upon the results of our study, reducing woody competition in the 2–5 m strata would improve habitat conditions for sexual reproduction, which could increase the potential for recovery of Michaux's sumac.