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大武口地区自1956年大搞植树造林以来,1979年普查有林面积5044亩,四旁植树17.2万株。对于防风固沙,改善小气候条件,绿化美化城市环境,保护农牧业生产起到了很大作用。但自1976年以来发生了星天牛严重危害。1979年～1981年对此虫的分布、危害情况、生物学特性及防治措施作了初步研究。一、发生和危害情况初步查明光肩星天牛在大武口地区发生极为严重。方圆面积约87.5平方公里;为害林木三千余亩,杨柳树木受害株率达85％以上。轻者枝梢枯萎,缺头少枝,重者树干遍布虫孔,成排成片枯死。以市区、大武口园林场、大武口公社最为严重。市区1976年以前
Dawukou area since 1956 vigorously afforestation since the 1979 census forest area of 5044 acres, 172,000 trees planted around. It has played a significant role in windbreak and sand fixation, improvement of microclimate conditions, afforestation and beautification of urban environment and protection of agriculture and animal husbandry production. However, Asclepius has been a serious hazard since 1976. From 1979 to 1981, the distribution, harm, biological characteristics and control measures of this pest were preliminarily studied. First, the occurrence and the initial identification of harm Haemonchus anguilla occurred in the Greater Wukou area is extremely serious. An area of about 87.5 square kilometers; damage more than 3,000 acres of trees, trees willow damage rate of more than 85%. The light branches withered, lack of head less branches, heavy trunk over the wormhole, rows into pieces died. In urban areas, Dayukou garden, Dawukou commune the most serious. Downtown before 1976