6/21/14: This week on "The Plant Detective:" Even today, many elderly Chinese still prefer a good ginseng root to health insurance. American ginseng (Panax quinquefolius) is used to aid digestion, treat diabetes, boost immunity, and balance qi, or life energy. More beneficial uses are part of traditional Chinese (and American Indian) medicine, and even more are under investigation. But in the wild, this valued plant is endangered; it matures slowly, and the combination of disappearing habitat, hungry deer, and overharvesting have taken a big toll. If you use American ginseng, make sure it's either cultivated, or ethically gathered.