Type of Distribution and Method of Density Estimation for Pantana phyllotachysae

In northern Fujian, the type of distribution of overwintering larvae and egg masses belongs to aggregation distribution, which is resulted from its biological characteristics and environmental heterogeneity. The relationship between site condition and pest density was studied, The results showed that its egg density was affected by the vegetation in the forest. And the density of egg and larvae decreases with the increase of crown density. The percentage of trees infested is positively related to the larvae and/or egg density. The formula is fitted for the expression of relation between pest density and percentage of trees infested. However, attention should be paid to the selection of appropriate high or low limits for the estimation of its population density.