Yushu can be used as a pesticide, which is mainly used to control pests and diseases. Only timely medication can control it, otherwise it will seriously hinder the growth of plants. Common pests are aphids and scale insects, which suck the juice of plants and cause them to turn yellow. It is suggested to spray 40% omethoate emulsion 1000 times. Common diseases are rot and leaf spot. The rotten part should be disposed of and sprayed with carbendazim for sterilization. It is suggested to spray 0.5%- 1% bordeaux mixture for leaf spot disease.