天幕毛虫喜食柞叶,在大发生年份可将柞叶全部食光,给柞蚕生产造成重大损失。1971年,辽宁省的岫岩、东沟两县此虫大发生,几天之内就将七、八个公社的蚕场柞叶吃光,迫使春蚕下山七、八百把,秋蚕少养两千余把。为了有效地防治天幕毛虫,我们利用多种药剂,对2—5龄的天幕毛虫进行药杀试验,取得了较好效果。一、药剂杀虫效果 (一)用亚胺硫磷防治:把25％的亚胺硫磷乳油用清水稀释成3,000倍、4,000倍、5,000倍液(含有效浓 The celestial caterpillars like to eat oak leaves, and the oyster leaves can be eaten all the year round in the big occurrence, causing heavy losses to tussah production. In 1971, in Xiuyan and Donggou counties of Liaoning Province, this pest occurred. Within a few days, seven or eight communes of the silkworm farm were eaten by the oak leaves, forcing the silkworms to go down seven or eight hundred and the autumnal silkworms were less cultivated More than two thousand. In order to effectively control the sky caterpillars, we use a variety of agents, 2-5 instar cents caterpillars kill test and achieved good results. First, the pesticide insecticidal effect (A) with the control of imipenem: The 25% of the diltiazem diluted with water to 3,000 times, 4,000 times, 5,000 times the solution (containing effective concentration