Regional genetic variation in turkey oak, Quercuslaevis

Abstract

Quercuslaevis Walt, (turkey oak) is a dominant hardwood tree in the sandhills communities of the coastal plain of the southeastern United States. Estimates of allozyme diversity for this species were typical of oaks (Hes = 0.184) and diversity within eleven sandhills populations was also relatively high (Hep = 0.178). Genetic diversity among populations was low (GST = 0.032), being about one third of the mean for other oak species. We interpret the interpopulation homogeneity as a relict of a previously more continuous distribution of longleaf pine (Pinus palustris Mill.)–turkey oak forest that constituted the dominant vegetation of the coastal plain prior to European settlement. Pollen-mediated gene flow among populations may be enhanced through acorn dispersal by blue jays (Cyanocittacristata L.).