The effect of site preparation treatment to the growth of acacia hybrids, Acacia mangium, A. auriculiformis plantation in Cam Thuy district -Thanh Hoa province

Abstract

Site preparation is an important silviculture treatment for intensive forestry; it contributes to the increase productivity and quality of plantation, especially intensive plantation of Acacia hybrids, Acacia mangium, and A. auriculiformis. In this study, three different site preparation treatments were used in site slope 20 - 25 degrees included: 1/ Plowing into rows, in each row was dig holes with size of 30*30*30 cm; 2/ Making terraces field with 1m wide along co ntour lines, the hole size of 40*40*40 cm; 3/ Dig holes with size of 40*40*40 cm. After 2 years, the average survival rate of Acacia hybrids reached 91.42%, average diameter at breast height (DBH) from 7.76 - 8.05 cm, the average height (H) from 6.09 - 6.63m, the average crown diameter (D crown) from 2.81 -3.33m, the best growing is treatment 3 and the worst growing is treatment 2. After 2 years, the average survival rate of Acacia mangium reached 87.52%, average diameter at breast height (DBH) from 6.36 - 7.76 cm, the average height (H) from 5.40 - 6.59m, the average crown diameter (D crown) from 2.00 -2.39m, the best growing is treatment 3 and the worst growing is treatment 2. After 2 years, the average survival rate of A. auriculiformis reached 85.10%, average DBH from 5.01 - 6.85 cm, the average height (H) from 5.56 - 6.59m, the average crown diameter (Dcrown) from 2.56 - 3.50m, the best growing is treatment 3 and the worst growing is treatment 2. Thus, all of three acaci species have the best growing in treatment 3 and the worst growing in treatment 2.