Abstract: The cotton locust,Chondracris rosea rosea DeGeer,is one of the most destructive insect pest of beef wood(Casuarina equisetifolia L.)in Kwangtung Province.In Dong-hai Forest Farm it damages about 150—200 ha.of trees every year.It has one generation per year and over winter in egg stage in the sandy soil.At the end of April and in the beginning of May next year,the hoppers or nymphs appear,emerge as adults usually from mid-June to late July,and die in the period from July to September. The most practicable control of this pest is,if the young hoppers appear from the soil,to spray with 6% BHC dust,if the old hoppers and adults climb up the tree,apply smoke "DDVP".