论文部分内容阅读
三北地区杨树害虫种类繁多,危害严重。对杨树生产造成很大威胁,尤其是植根苗造林早期发生虫害,直接影响到造林的成活率和保存率以及木材的工艺价值。为害植根苗造林的早期害虫主要有:黑级金龟(Malad。"tallyMOtschu切勿),该虫一年一代,成虫在土中越冬。4月中、下旬出
Poplar pests in the three northern regions a wide range of serious harm. It poses a great threat to the production of poplar, especially the early occurrence of plantation seedling afforestation, which directly affects the survival rate and preservation rate of afforestation and the craft value of wood. Early pests for planting rooted shoots include: black-tailed turtles (Malad. "TallyMOtschu not), the insects a year, adult wintering in the soil .4 mid to late out