Natural restoration of forest after selective logging in the Central Vietnam

Objective: To identify the impact of selective logging on the characteristics of reforestation in Central Vietnam. Research work carried out in 2017 in areas of selective logging of Huong Khe district, Ha Tinh province, at altitudes 200–300 above sea level. We studied 4 of the most economically valuable regenerated tree species from the 1st layer: Vatica tonkinensis, Madhuca pasquieri, Hopea pierrei, Erythrophleum fordii in the areas of felling 2005, 2008, 2010 and 2012. The intensity of logging was about 25–30 % of the stock. The density of undergrowth on felling areas increased compared with the control, and this increase two years out of four statistically significant for Vatica tonkinensis and Hopea pierrei. The undergrowth of Vatica tonkinensis is different from other species by stable number at logging sites of different year. Hopea pierrei number of undergrowth increases with age of cuttings. The photophilous undergrowth of Erythrophleum fordii, in contrast, has a high density in the 5–7-year- old cuttings area. The density of Madhuca pasquieri is not significantly different from the control. The occurrence of undergrowth is also higher in cutting areas. The total share of four breeds in the total composition of undergrowth is 36–41 % and it doesn’t change much with the age of felling. On the control this fact is not observed. The share of undergrowth of Vatica tonkinensis and Hopea pierrei is increasing in logging areas compared to the control. The number of undergrowth of all four species decreases with increasing of height. As a rule, there are a litle bit more small ones at the cutting areas compared to the control irrespective of the species; the largest one has the opposite tendency. In general, in the areas of selective felling with age 5–12 years, the undergrowth of the most valuable tree species differs from the control in the greater density, occurrence and share in the total composition of the undergrowth.