Abstract: Gravitarmata margarotana Heinemann and Petrova cristata walsingham are serious forestinsect pests in Cuizhou province, they mainly injure the cones of pine trees, sometimes damage the shoots too. In recent years they have frequently occurred in the seed orchard of masson pine of Henpo forest farm in Huangping county, the large amount losses of cones are caused by them every yrear. From 1990 to 1992, their mixed population saptial distribution pattern and sampling technique in the seed orchard had been examined by means of seven aggregation indices, and regression analysis methods of Iwao, Taylor,and Lan Xingping etc. in Henpo forest farm of Huangping county. The results show that the distribution pattern of mixed population of pine seed borers belong to the aggregation. The reasons of aggregation are caused by borers biological characteristics and environmental factors. The linear related degree of La-m regression model is optimum among the five models.According to the saptial distribution pattern of cone borers, the sequential sampling equations and determining maximum sampling number for cone borers of pine tree seed orchard were presented by authors in this paper.

Key words: Masson pine, Seed orchard, Cone borer, Saptial dietribution pattern, Sampling technique