EVALUATION OF GROWTH, PRODUCTIVITY AND SELECTION PLUS TREE OF SOME INDIGENOUS TREE SPECIES IN QUANG NINH PROVINCE

Abstract

The results of the evaluation of the plantation forests of some native tree species such as Castanopsis cerebrina (Hickel & A. Camus) Barnett, Magnolia mediocris (Dandy) Figlar and Cunninghamia lanceolata (Lamb.) Hook. in Quang Ninh province show that the 13-year-old Castanopsis cerebrina (Hickel & A. Camus) Barnett plantation forest in Dong Lam commune, Ha Long city has a survival rate of 81.8%, the average diameter is 18.4 cm, the peak height is 16.0 m, and the yield is 10.7 m³/ha/year. Based on growth criteria and tree trunk quality, 14 plus trees were selected with diameter exceeding 35.7 - 77.5% and peak height exceeding 14.9 - 46.0%. compared to the population average. The 13-year-old Magnolia mediocris (Dandy) Figlar plantation forest in Dong Lam commune, Ha Long city has a survival rate of 83.3%, an average diameter of 16.2 cm, a peak height of 13.1 m, and a yield of 6.9 m³/ha/year and selected 13 plus trees from this forest with diameter exceeding 26.4 - 44.6% and peak height exceeding 10.3 - 24.1% compared to the population average. The 13-year-old Cunninghamia lanceolata (Lamb.) Hook. plantation forest in Thanh Son commune, Ba Che district has a survival rate of 61.9%, an average diameter of 13.5 cm, a peak height of 16.9 m, and a productivity of 14.4 m³/ha/year and selected 12 plus trees with diameter at breast height exceeding 45.3 - 88.3% and peak height exceeding 23.4 - 50.9% compared to the average criteria of the population.