ADAPTIVE CLUSTER SAMPLING FOR FOREST INVENTORIES

Adaptive cluster sampling is shown to be a viable alternative for samp ling forests when there are rare characteristics of the forest trees w hich are of interest and occur on clustered trees. The ideas of recent work in Thompson (1990) have been extended to the case in which the i nitial sample is selected with unequal probabilities. An example is gi ven in which the initial sample of trees is selected with probability proportional to tree basal area. If a characteristic of interest is ob served on a sample tree, additional trees within a fixed distance of t he sample tree are also included in the sample.