Natural regernaration after shifting cultivation in the Ia Grai Protection Forest area, Gia Lai province

Abstract

This article presents the study results on the forest natural regeneration after shifting cultivation at the Ia Grai Protection Forest, including: density and species composition of regeneration trees; regeneration tree distribution by height class; quality and origin of regeneration trees and proposed silvicultural measures for forest restoration after slash and burn cultivation at the Ia Grai Protection Forest. The results show that the longer fallow period, the simpler the species composition. The number of regeneration species accounted in fallow periods of less than 5 years, 5 - 10 years, 10 - 15 years and over 15 years were 21, 16, 15 and 13 species, respectively; The regeneration tree densities were about 9,500; 5,000; 4,800 and 4,200 trees/ha, respectively. Tree regeneration distribution by height class tends to decrease from height class < 1m to height class > 3m. The rate of seedlings was about 80% and shoots was 20%. The rate of the good quality trees was from 10.2% to 26.6%; the average quality was from 8.1% to 33.3% and the bad quality was from 40% to 73%.