Abstract

Wild-harvested American ginseng (Panax quinquefolius L.) is traded internationally for its medicinal properties, and North Carolina is one of the United States’ leading exporters of wild American ginseng. Harvest is regulated by state, and states must demonstrate that harvest is not detrimental to ginseng’s long-term viability, so to determine if North Carolina regulations adequately protect ginseng, the demographic characteristics of five local populations were examined. Annual censuses were conducted for 2 years, tracking individual plants and recording leaf number and flower presence or absence. In the second year, data on each plant’s fruit production were collected, and seed production was estimated using a published value of average seeds per fruit. Demographic data were used to construct a population matrix model for each population, and growth rate (with 95% confidence intervals), stable size distribution, and the elasticity of growth rate to transition probabilities were calculated. Three of the five populations were declining in the absence of any harvest, so for these populations, times to extinction were projected. The effects of increasing harvest rates (up to 100% of legally harvestable individuals) on growth rate were projected for the other two populations. The SC population was most resilient to harvest, with a growth rate of 1.18, while the MP population was more vulnerable. There was no clear distinction between growing and declining populations in either stable size distribution or elasticity of growth rate to transition probabilities. Sampling will continue so that in several more years, a more robust data set can be used to provide more reliable conclusions.

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