Soil and Leaf Nutrient Analysis of the Endangered Herb, Baptisia arachnifera, in Georgia, United States

A better understanding of the soil conditions and management practices of an endangered plant may help develop improved restoration and conservation plans. Proper soil and plant nutrient management is critical for the plant’s growth and health. To accomplish this goal, it is important to understand the nutrient status of the plant and the soil in which it is growing. Baptisia arachnifera (Hairy Rattleweed) is an endangered herbaceous legume for which basic nutrient information is not available. This species occurs only in Wayne and Brantley Counties of Georgia, United States and is found primarily in pine plantations. This study was conducted to investigate the plant and soil nutrient content of B. arachnifera populations. Leaf and soil samples were collected from six sites where the species was present and soil samples were collected from six sites where the species was historically absent. Samples were analyzed at the University of Georgia and Georgia Southern University, GA. Results indicated that leaf nutrients including aluminum, boron, copper, iron, manganese, sodium, and zinc ranged from 42.5–96.6, 18–33.1, 3.6–17, 48.8–79.9, 27.8–191.2, 1491.1–5964.1 and 10.6–19.9 ppm, respectively and differed significantly among sites. Differences were found in carbon, calcium and nitrogen, concentrations and it varied from 482–12969, 348–870 and <5–99 ppm, respectively. As most of the remaining populations exist in commercial pine plantations, timber management practices such as tillage, soil preparation, fertilizer application and harvesting may affect the nutrient status of soil and plant tissue. This study gives a baseline information about leaf nutrient content of B. arachnifera and relevant soil nutrient information, which may have implications to conservation and restoration strategies for this endangered species. Further research should be conducted to understand how soil nutrient availability may influence the leaf nutrient status and population distribution of B. arachnifera.