杨牡蛎介壳虫是通化市多年来杨树主要害虫之一,不仅在大面积速生丰产林中有所发生,就是在城区街道绿化杨树也普遍发现。据一九八三年来,在通化市二十多华里长的新华大街、建设大街两侧绿化杨树中调查,七至十五年生杨树,受杨牡蛎介壳虫为害较为严重,群集侧枝基部,并向上扩展,虫口密度大的树木,枝叶长势不茂,被害枝条干枯,甚至整株死亡(见表1)。 Yang Oyster cocoon is one of the main pests of poplar in Tonghua City for many years. It not only occurs in large-scale fast-growing and high-yielding forests, but also poplar trees in urban streets are commonly found. According to a survey conducted in 1983 by Xinhua Street, a metropolis of more than 20 years in Tonghua City, green poplar trees on both sides of the Main Street, poplar trees aged seven to 15 years were more severely damaged by Yang Oyster scale insects, with colony at the base of branches and upward Expansion of dense population of trees, branches and leaves are growing, withered branches were dry, or even whole plant died (see Table 1).