Sampling techniques and the use of Tang's procedure in insect population dynamics studies

Some calculations were performed usingTang 's method as an aid in planning experiments for studying the population dynamics of the Jeffrey pine beetle. The population dynamics studies were aimed at detecting the importance of specific effects, e. g., tree diameter, tree height. TheTang procedure is a method of estimating the sample size required to detect effects of a given magnitude with analysis of variance tests. Using this procedure some sample calculations were performed which indicated the sample size needed, and the efficacy of different strategies of improving the results, e. g., increasing the number of trees sampled versus increasing the area of the tree sampled. The statistical parameters used in the calculations were estimated from some preliminary sampling data. Use of this procedure is recommended in insect population studies as a method of optimally planning experiments, and as a method of making precise conclusions about the significance of specific effects.