Ginseng has wide range adaptability to ecological environment and vast distribution. Through analysing the conditions of the main producing area of ginseng, we chose several factors from a lot of factors of ecological climate conditions as follows:
1. Height above sea level;
2. Temperature in the hottest month;
3. Annual rainfall;
4. Relative humidity;
5. Frost-free season.
Five dependent functions of the above factors were established by fuzzy set theory. A formula:
is suggested for calculating the integrated evaluation index. Five regions of ginseng ecological climate in Jilin Province were classified. Authors consider: the most adaptable region for ginseng cultivation is near the east and west sides of the main peak of Changbai Mountains (at height above sea level 400–900m) and it can also be planted from east till Xian Jing Nan Dao, Xian Jing Bei Dao, Liang Jiang Dao of north of Korean. In the region of low latitude, it is usual to raise the height above sea level of ginseng plantation in order to suit with temperature. The formulas for the height of upper and lower limit are given as: