ABSTRACT
Combined with practical experience, a stock investigation method of medicinal plants is approached from different angles, such as setting up the sample field and quadrant, doing the fieldwork, calculating the stock and annual possible gathering volume, etc. Depending on the geographical distribution features of the plants, the sample field are pointed out on topographic maps (1: 50 00 or 1: 10 000). Quadrants are set up at random or regularly according to the species and density of the plants. The locat ion, area, slop orientation, gradient,elevation, and vegetation of the sample field, also the area of quadrant and the amount of plants investigated, should be carefully noted down during the fieldwork .The quadrants are classified according to their slop orientation and gradient, then convert the recorded amonut of plants in quadrants to the amount of plants per square kilornetre. The stock of Per square kilometre is equal to the volume of the amount of the plants in per square kilometre divided by the amount of the plants per kilogram. The stock of per square kilometre multiplied by the area of earth's surface is the stock volume, which should be classified by the slop orientaion and gradient. The sum of the volunes is the total stock of a kind of plant.As to gather and make use of the medicinal plants in a gathering circle period, the annul possible gathering volume should be calculated as the stock volume of the plant divided by the gathering circle period.