采用聚集度指标法及平均虫口密度与平均拥挤度回归检验法 ,以 3种受害程度的云南松林为研究对象 ,研究了蛀梢期纵坑切梢小蠹在树冠上东、南、西、北 4个方位和上、中、下 3个层次的分布 .结果表明 :在不同受害程度的林分内 ,纵坑切梢小蠹在整个树冠上及树冠的不同方位、层次均属聚集分布 .聚集的主要原因与其自身的取食行为有关 ;轻度受害林分的南面中层、中度受害林分的东面上层、重度受害林分的东面中层最能代表整个样地的平均虫口密度 ,确定为最适抽样部位 ;分别建立了最适抽样表 ;并制定了中度受害林分的序贯抽样方案 ,确定不同允许误差时的最大抽样量 Using the aggregated index method and the mean population density and the average crowding degree regression test, taking three kinds of damage degree of Yunnan pine forest as the research object, we studied the effects of the deciduous beetles on the canopy at east, south, west and north 4 azimuths and distributions of upper, middle and lower strata.The results showed that in different stands of afforestation degree, Pinus taiwanensis was aggregated and distributed in different azimuths and levels on the whole canopy and canopy. Mainly due to its own feeding behavior; the middle layer of the south middle layer of moderately harvested stands, the upper layer of the middle layer of moderately harvested stands, and the middle layer of the middle layer of heavily harvested stand can best represent the average density of pests in the entire plot, As the most suitable sampling site; established the most appropriate sampling table; and developed a series of sequential sampling program of moderate damage, to determine the maximum allowable sampling error