Conservation Biology of Baptisia arachnifera (Fabaceae)

 Baptisia arachnifera is a unique Georgia endemic species of plant found only in a 10-square mile area near Jesup, GA. Nearly all the populations of this species are declining and found on private timberland used for commercial production of timber and pulp. An experimental planting of this species at the VSU Lake Louise Field Station was started in the late 1980’s by the former VSU Biology Dept. chairman Wayne Faircloth, a noted botanist of the Georgia coastal plain and the scientist who wrote the recovery plan for this species. In 2004, the Ecology class mapped and measured the remaining individuals of this outplanting. We found that the population had slightly increased. In 2005, I supplemented the existing plants with plants grown from seed obtained from the University of Georgia Botanical Garden, who maintain an ex situ collection of this endangered species. Plans are to continue supplementing the experimental population and to establish 8 subpopulations of at least 50 individuals each within the Lake Louise Field Station. The subpopulations will be exposed to different burn schedules (no burn, burn every year, burn every 3 years, burn every 5 years) to examine the influence of fire on the long-term demography of the species. Potential MS topics include 1) the reproductive biology of the species, including breeding system and pollinator studies, seed germination and longevity studies, the impact of a seed predator on reproductive success, the role of light, nutrients, and competition on individual plant growth and flowering, the clonal structure of the species, and the demography of the species.

            A second area of potential research is the putative hybridization of the species with a co-occurring native species present at Lake Louise, Baptisia lecontei. Because B. arachnifera is outside of its native range, it has come into contact with a native species. Several putative hybrid individuals have been found at Lake Louise that suggest B. arachnifera and B. lecontei have interbreed. Definitive analysis of these individuals should include crossing experiments, cytotype analysis (number of chromosomes), chemical analysis, and genetic analysis (allozymes, DNA). Additional research could include developing crosses between B. arachnifera and other potentially related southeastern species (B. perfoliate, B. simplicifolia). In addition, several ecological questions can be pursued including the relative fitness of the hybrid versus the parents, the relationship between distance and probability of hybrid formation, and the rate of backcrossing between hybrids and the parents.