Demographics andCronartium appalachianumRust Disease Assessments in Three Tennessee Populations ofBuckleya distichophylla(Nutt.) Torr. (Santalaceae)

Abstract

ABSTRACT A demographic census and disease assessment was conducted in 2007 and 2015 in three Tennessee populations of the dioecious shrub, Buckleya distichophylla (Santalaceae). Population sizes were relatively stable over time and plant heights and numbers of stems per clump were similar among populations. Seedlings were present in all populations, where they represented 14–19% of individuals. Two populations had an equal male:female sex ratio, but a third population was male-biased. Nonflowering individuals comprised 33–41% of individuals in a population. The majority of plants in all populations had high vigor. Spatial analyses revealed clusters of seedlings in two populations and a cluster of low-vigor plants in one population. Cronartium appalachianum, a rust fungus dependent upon Pinus virginiana and B. distichophylla as primary and alternate hosts, respectively, was present in all populations with prevalences on B. distichophylla of 19–29%, but there was no spatial clustering of disease in populat...