A mission of the Degradation Effects Program (DEP), formerly Joint Environmental Effects Program (JEEP), is to extrapolate estimates of lethality and munition effectiveness in DEP test environments to Southeast Asian environments. If these extrapolations are to be reliable it is imperative that the environmental conditions of the test areas be similar to those of Southeast Asia. Accordingly, objective comparisons must be made of DEP test environments and Southeast Asian environments. This report describes and compares some significant vegetation structural characteristics of two selected DEP sites in the Pina and Balboa forests in the Panama Canal Zone (CZ) and four selected sites in two forests and two rubber plantations in Thailand. (Author).