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众所周知,松毛虫是松树的一大害虫。可是,在昆明地区,还危害圆柏和侧帕,幼树被害后死亡率迭22％,成年树木受害后平均直径生长降低45％。圆柏是深受广大群众喜爱的常绿树种,在全省发展都很快。由于圆柏纯树造林面积越大,发生病虫害的可能性也就越大。所以,近几年来,危害圆柏树的云南松毛虫不断发生,成为圆柏树的一种危险性食叶害虫,应当引起重视,1981—1984早期间,省、市政府机关在官渡区分洪河堤上栽植了约7公里长的圆柏树护堤林带,长势很好。可是1985年个别河段的圆柏发生了云南松毛虫,1986年蔓延到整个河堤两岸。由于采取了有效的防治措施。才使这一林带免遭损失。据观察,危害昆明地区圆柏
It is well known that pine caterpillars are a major pest of pine trees. However, in Kunming, Sabina przewalskii and Pampanga are also harmed. Mortality after sapling is 22% and the average diameter growth of adult trees is reduced by 45%. Sabina is an evergreen tree favored by the general public and has developed rapidly in the province. The greater the afforestation area, the greater the likelihood of pests. Therefore, in recent years, endangering cypress trees of Yunnan pine caterpillars continue to become a drupe of a dangerous leaf-eating pests, should pay attention to, 1981-1984 early period, provincial and municipal government organs in the Guandu distinction on the flood embankment Planting about 7 km long circular cypress embankment forest belt, growing well. However, in 1985 individual cyclone yunnan pine caterpillars, in 1986 spread across the embankment. As a result of effective prevention and control measures. Only this forest belt from loss. It is observed that the damage to the Kunlun region Sabina