Chemical controls can dramatically reduce pest populations in the short term, yet by unavoidably killing (or starving) natural control insects and animals, cause an increase in the pest population in the long term, thereby creating an ever-increasing problem.
化學防治可以在短期內大幅度減少害蟲種群，但不可避免地會殺死（或餓死）自然控制昆蟲和動物，從長遠來看，有害生物種群數量增加，從而造成日益嚴重的問題。