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我省兴文县先锋国营林场赵家坪工区,1957年造的1,000多亩杉木林,1967年开始有3亩发生根腐病,以后年复一年地发展,到1971年已蔓延至900多亩,其中病害严重的有600多亩。病树的针叶普遍发紫变黄,新梢萌发率低;根系出现不同程度的腐坏,严重者须根全部脱落;侧根皮层污黑似水浸,易剥离。病害从6月开始发展,7、8月急剧加重并出观成片枯死,8月达高峰,后又渐稳定。据1971年调查:5月份发病30多亩,6月份发展到200多亩,8月份后扩大到900多亩,全工区的杉木林受到毁灭性的威胁。
Xingwen County, our province pioneer Zhaojiaping Pioneer State Forestry Center area, in 1957 made more than 1,000 acres of fir forest, there are 3 acres of root rot occurred in 1967, after years of development, to 1971 has spread to 900 acres, There are 600 acres of serious disease. Diseases of conifers commonly purple hair yellow, shoots germination rate is low; roots appear different degrees of spoilage, in all cases, all fibrous loss; lateral cortical subsidence is like black, easy to peel. The disease started to develop from June, with a sharp increase in July and August and a withered appearance. It peaked in August and then gradually stabilized. According to a survey conducted in 1971, the incidence of more than 30 mu in May increased to 200 mu in June and then to 900 mu in August. The entire planted fir forest was devastated.