The growth period, plant ages and essential oil content of fruits from different sides or sloping land, and essential oil rates and aldehyde content extracted during processing were studied at Ziyun and Rongjiang counties in 1984-1985. The results show that fruit yield and essential oil content from 7-10 years plants, and contents of essential oil and aldehyde from fruits collected at the red fruit stage are the highest. At the same time, the improved extraction method of processing on heavy fire and shorte...