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晋州市现有速生丰产林1200公顷,四旁树和农田防护林1800公顷,林木总面积达3000公顷(不含经济林),占全市总面积的4.9%。由于造林和管理上措施不当,林木病虫害日趋严重,林木正常生长受到影响,不仅严重阻碍了林木生态防护效能的发挥,也给林农造成了极大的经济损失。病虫害发生现状晋州市林木病虫害的发生面积和危害程度呈逐年上升的趋势,据2004年调查,病虫害发生面积为750公顷,病虫害发生率达25%。种类主要有:桑天牛、光肩星天牛、柳毒蛾、杨扇舟蛾、大袋蛾、腐烂病和溃疡病。其中,以食叶害虫发生最为严重,占发生面积的70%。通常整片林木树叶被害虫吃光,树木生长缓慢,个别林分多次被害,林木生长停止,部分林木枯死。
Jinju City now has 1,200 hectares of fast-growing and high-yield forests, 1,800 hectares of trees and farmland shelterbelts, and a total area of 3,000 hectares (excluding economic forests), accounting for 4.9% of the total area of the city. Due to improper measures in afforestation and management, the pests and diseases of trees are becoming more and more serious, and the normal growth of trees is affected, which not only seriously hinders the development of forest ecological protection, but also causes great economic losses to forest farmers. Status of Pests and Diseases The occurrence area and the degree of harm of forest pests and diseases in Jinju City have been increasing year by year. According to the 2004 survey, pests and diseases occurred in an area of 750 hectares and the incidence of pests and diseases was 25%. The main types are: Morus alba, Atractylodes lanceolata, Liu poison moth, Yang Fan moth, big bag moth, rot disease and ulcer disease. Among them, the most serious leaf-eating pests, accounting for 70% of the area. Often the whole forest tree leaves are eaten by pests, trees grow slowly, and several individual trees are killed. Growth stops and some trees are dead.