SOME SILVICULTURAL CHARACTERISTICS OF Quercus platycalyx Hickel & A.Camus OF EVERGREEN BROAD - LEAVED FOREST IN PHU THO PROVINCE AND TUYEN QUANG PROVINCE

Abstract

Q.platycalyx is a large tree, widely distributed from Nghe An to Northern provinces of Vietnam. Its light yellow wood is used in construction, furniture, and mine pole. It meets the requirements of forest trees for supporting large diameter wood in accordance with the Government's orientation for large timber trees. The results of the study on evergreen broad - leaved forest in Phu Tho province and Tuyen Quang province showed that the species is the dominant tree species at the crown level. Tree density of secondary forest distributed Q.platycalyx is from 388 to 708 trees per hectare in Phu Tho province and from 252 to 384 trees per hectare in Tuyen Quang Province, denisity of Q.platycalyx is from 12 to 96 trees per hectare in Phu Tho province and from to 36 trees per hectare in Tuyen Quang province. Species of Canarium album, Erythrophleum fordii, Cinnamomum burmanii and Gironniera subaequalis in Phu Tho province and Canarium album, Pygeum arboreum, Machilus bonii, Ailanthus malabarica, Peltophorum tonkinese, and Lysidice  rhodostegia in Tuyen Quang province  are the most closely related species and are most supportive for Q.platycalyx. The canopy structure has main layers, the number of trees in theo forest stand is mainly concentrated in the main canopy layer (61.9 - 92.7%), Q.platycalyx is mainly distributed in the dominance layer and the main canopy layer. Species of Q.platycalyx has very good natural regeneration ability, its seedling is one of dorminant regenerating seedling species in these secondary natural forest area.