Abstract:Different parts of twenty dominant plant species in five plantation communities on the subtropical hilly lands in Heshan of Gunagdong as well as the li tters from three of the five plantation communities were sampled, and their gros s caloric value (GCV) and ash content were measured by using a PARR-12 81 oxygen bomb calorimeter and a muffle furnace. Based on the measurements, the ash-free caloric value (AFCV) of the samples was calculated, and the characteri stics of caloric value and ash content of the samples, according to plant part, individual, and plant growth form, were analyzed. The results showed that the GC V and AFCV of leaf, branch, stem wood, stem bark, and root were in the range of 107〖KG-*2〗-〖KG-*7〗2217 kJ·g-1 and 1389〖KG-*2〗-〖KG-*7〗2304 kJ·g-1, respectively. The GCV and AFCV of leaf were significantly higher than those of other parts (P<005), and the individual plant’s weighted m ean values of GCV and AFCV were in the range of 1424〖KG-*2〗-〖KG-*7〗194 3 and 1663〖KG-*2〗-〖KG-*7〗2099 kJ·g-1, respectively. The mean AFCV of plantation communities was in the order of tree layer (1955 kJ·g-1) >shrub layer (1946 kJ·g-1)>herb layer (1877 kJ·g-1), with indigenous coniferous tree (1986 kJ·g-1)>indigenous broad-leaved tre e (1955 kJ·g-1) > exotic eucalyptus (1918 kJ·g-1), while the m ean ash content was just the opposite. In Acacia mangium, coniferous, and Schima plantation communities, the GCV and AFCV of litters were higher than those of various plant parts (P<001). The litter-falls in A. mangium and coniferous plantations had higher mean GCV and AFCV than the litters and fr esh leaves of tree layer, while the fresh leaves of tree layer in Schima plantat ion showed higher mean GCV and AFCV.