Study on the Spatial Distribution Type of Tomicus piniperda During the Period of Feeding Shoot

A study on the spatial distribution type of Tomicus piniperda in the crown of yunnan pine during its shoot feeding period proves that in both different direction and the layer of the crown in different damaged levels of yunnan pine forest,the spatial distribution type of the pest is aggregation type.The aggregation reason lies in its feeding behavior.In the minor damaged level yunnan pine forest,the middle layer in the south of the crown,in the medium damaged level forest,the upper layer in the east of the crown,and in the serious damaged level,the middle layer in the east of the crown are the appropriate position to get samples.The most appropriate sampling amount are established in different damaged forest.The sampling scheme of the medium damaged forest is designed and determine the largest amount of sampling on different admitted error level.