Study on the Population Dynamics Dendrolimus punctatus in Anhui Province

Samplings were conducted continually in large area (more than G5 hectares) from 1981~1989, the life table of 22 generations of pine caterpillar, Dendrolimus punctatus has been established. The sampled forest is typical in Anhui. From this life table, a life systematical model has been worked out. From the model, it can be seen that there are three key periods in population dynamics and that three submodels have been obtained. The key factors in population dynamics are original population density, feeding conditions, the weight of female pupae and sex ratio. The only climatic factor that affects population dynamics is the average relative humidity (%) in September. The sampling method used is in accordance with the method used in forest production. It is believed that this systematical model is practical in pest management, because no artificial simulation has been used in sampling and so the artificial influence has been eliminated.