Evaluation and prediction of ecological suitability of medicinal plant American ginseng ( panax quinquefolius )

American ginseng is a medicinal plant with large market demands, however, its producing areas are shrinking because of the continuous cropping obstacles in China. Therefore, it is urgent to establish a suitable model to determine the new producing areas. Here we evaluated and predicted the suitable areas of American ginseng using the maximum entropy model (MaxEnt). Based on the 37 environmental variables over thirty years from 1970 to 2000 and...