STUDY ON SILVICULTURAL CHARACTERISTICS OF PSEUDOTSUGA BREVIFOLIA W. C CHENG & L. K. FU SPECIES IN NGUYEN BINH DISTRICT, CAO BANG PROVINCE

Abstract

The study was designed to identify some structural features and regeneration in which Pseudotsuga brevifolia was being distributed. The study was conducted in 2 communes of Nguyen Binh district, Cao Bang province, with 30 sample plots with the sample area are ​​200m²/plot, 120 plots with 25 m²/plot, the study was conducted by the silviculture investigated method. The results showed that: there were 3-5 species that involved in forest composition, Pseudotsuga brevifolia was living with state of being dominant in studied sample plots with IVi% index being the highest. Forest density varied from 518 to 612 stems/ha, Pseudotsuga brevifolia achieved the highest of density with number of stems being from 265 to 377 stems/ha. There are 5-6 species that involved in forest regeneration composition, Pseudotsuga brevifolia achieved the highest of the rate composition of 27.81% - 36.29%. The density of species P. brevifolia regeneration is from 362 to 529 stems per hectare. The quality of regeneration Pseudotsuga brevifolia is mainly good and medium. The rate of regeneration trees from seeds obtains. Mostly is at height levels <50 cm and> 100 cm. The research results are the basis for proposing solutions to preserve and develop this rare species.