Black cohosh (Actaea racemosa L.) is an herbaceous plant increasing in popularity and value as a result of its medicinal uses. The new found increase in demand has caused an increase in the harvesting pressure of black cohosh from wild populations, while cultivation to alleviate this pressure has been minimal. Surprisingly, there are no studies that describe the species habitat attributes in a quantitative manner, even though a number of reports document qualitative evidence of its preferred habitat. Our study focused on examining the ecology of black cohosh and its preferred sites. Such ecological knowledge can improve the chances of successful cultivation, improve harvesting success rate, and provide information for sustainable management of this plant. We examined the occurrence, abundance, and flowering performance of black cohosh in plots on the southern Cumberland Plateau in northern Alabama. We used transects along the plateau escarpment and established plots in locations where black cohosh was encountered. At each plot we determined tree species, density, and stocking and measured tree basal area, percent canopy cover, slope, and aspect, among other variables, to relate them to the black cohosh abundance and performance.
Results/Conclusions
The average basal area within the plots where black cohosh occurred was 104 ft2/ac and the average tree crown cover was 93%. We found the plant in both open areas and in closed canopy conditions. Very few of the studied predictor variables appeared to be significantly associated with the density of black cohosh on the plots or with its flowering performance. There was a positive association between the number of flowering bolts and black cohosh cover. Additionally, the species cover was twice as dense on the study plots with north-eastern aspect as on the plots with south-western aspect. Nevertheless, it was clear that the species was present on all aspects. Our work represents the first quantitative measure of black cohosh abundance and flowering performance and links it with habitat attributes. Our work indicates that the species may be much more of a generalist than previously thought, which has important implications for harvesting, conservation, and cultivation.
