【摘要】 湿地松粉蚧在湿地松林间呈聚集分布。湿地松粉蚧虫口密度在湿地松树冠东、南、西、北向之间无显著差异，而在树冠上、中、下层之间有极显著差异，虫口密度大小是树冠上层＞中层＞下层。５种抽样方法中，以双对角线法最佳，其次为Ｚ字形法；每１／１５ｋｍ２湿地松抽查样树１０株为适宜。更多还原

【Abstract】 The distribution of the Loblolly Pine Mealybug Oracella acuta(Lobdell)exhibited an aggregation pattern in Pinus elliottii pine plantations.In the samecrown level,the population density of Oracella acuta did not differ significantlyamong the eastern, southern,western and northern shoots.The populationdensity was highly significantly different among the three crown layers,namely,high layer>mid-layer>low iayer.Different sampling methods were compared,the intersecting diagonal method was found to be the best and the Z-shapedmethod the next best.One hundred and flfty trees per ha were sampled.更多还原