1962年冬季浙江省桑树发生大量死亡,而1963年入春以后,死亡更为急剧,尤以杭嘉湖地区最为严重。据嘉兴专署农业办公室在吴兴县镇西公社典型调查了554株(面积2.41亩),共死亡152株,死亡率达27.4％,其中1962年冬季死亡69株,为死亡总数的12.4％,1963年春季死亡83株,为15％;又如在嘉兴县余新公 In the winter of 1962, a large number of mulberry trees died in Zhejiang Province, but after the spring of 1963, the death was even more rapid, especially in the Hangjiahu area. According to Jiaxing agency agricultural office in Wuxing County town communes surveyed 554 strains (area 2.41 acres), a total of 152 deaths, the mortality rate of 27.4%, of which 69 deaths in 1962 69 strains, the total number of deaths of 12.4% in 1963 83 deaths in spring, 15%; another example in Jiaxing County Yu Xingong