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采用标准地调查和单株调查的方法 ,研究了红脂大小蠹的发生和危害规律。结果表明 :红脂大小蠹主要为害油松的基部和根部 ,多为胸径 7 5cm以上、树龄 3 0年生以上的树木 ,幼龄树受害很少 ;海拔85 0m以上的树木受害重 ,且随海拔的增高危害加重 ;路边树木受害最为严重 ,其次是山顶 ,林缘树木受害较轻 ,林内树木受害最轻 ;在不同坡向分布的树木 ,阴坡受害大于半阴坡 ,半阴坡大于阳坡 ;此外 ,该害虫一般侵害树势衰弱的林木 ,随着树势衰弱程度的增加 ,其危害程度加重 ,树体内害虫数量与树木的衰弱程度呈线性相关 ,其方程为Y =1 3 3 2X -1 6 2 5 ,此方程可以用来推断红脂大小蠹可能发生的程度。
Using standard survey and single plant survey methods, the occurrence and harm of red beetles were studied. The results showed that the main species of Pinus tabulaeformis mainly damaged the base and root of Pinus tabulaeformis, mostly trees with DBH more than 30 years old. Young trees suffered little damage. The trees above 85 0m above sea level were seriously injured, Of the trees in the different slopes, shady slope damage is greater than half shady slope, half shady slope is greater than the positive In addition, the pest generally infects trees with weak bonsai trees. With the increase of the decay of trees, the degree of harm increases. The number of pests in trees is linearly related to the degree of decay of trees. The equation is Y = 1332X -1 6 2 5, this equation can be used to infer the extent of possible occurrence of red beetles.