In 1961, cocoa was a recently introduced crop to North Borneo. It was typically grown in large clearings and faced severe damage from pests such as cocoa loopers, bagworms, cossid borers. In addition bee bugs, a pest which was new to science, was damaging the pods. The fields were heavily and repeatedly sprayed with insecticides, sometimes including organo-chlorides such as DDT, but with little intended effect. In their original environments, natural enemies would have controlled these pests, but even those enemies in North Borneo were dying off from the use of pesticides.
Recognising that the pesticides were not working, all spraying was stopped and soon after the branch borer and cocoa looper came under control from parasitic wasps. The bagworms were soon controlled by the use of highly selective pesticides, and eventually by a parasitic fly. Destroying a large secondary forest tree, the borer’s host, largely eliminated the rink bark borer population. Within a year, all pests were satisfactorily controlled.