Abstract:

A series of Masson pine experiment stands were established in Taijiang County of Guizhou Province.The stands included main technical processes of growing Masson pine plantations.The purpose of establishing the stands was to study the effects of different silvicultural techniques for growth of young Masson pine plantations.Based on the yearly measures of permanent plots of the stands for 8 years, and the statistical analyses of the measured data, the results showed that selection of different sites and seed origins, and planting density were the most important factors influencing growth of young Masson pine plantations among all main silvicultural techniques.Size of planting holes had more obvious effect on the growth of the young stands.Fertilization of the young stands had effect in a certain extent. Soil preparation way and young stand tending had no obvious effect on growth of the young plantations.Directive cultural techniques of growing the industrial Masson pine plantaions used in the trial area were preliminarily developed on the bases of above study.The techniques are as follows:Planting site lower, mid-lower and middle of mountain slopes, site index is above 16.Seed origin select seed origin of Gupeng and Tongmian in Guangxi Province.Planting density on middle quality site, building ~ timber : 1665 ~ 2500 tree/hm², pulpwood : 3330 ~ 4440 tree hm², fiber and chip board timber : 4995 ~ 6660 tree/hm².Soil preparation way spot preparation.Size of planting hole 40cm × 40cm × 25cm.Fertilizing young stand under the conditions of serious P deficiency calcium and magnesium phosphate used as base fertilizer, above 60g/hole (above 266kg/hm²); compound fertilizer used as topdressing, above 30g/hole (above 133kg/hm²).Young stand tending cut weeds and shrubs twice per year for 3 years.

Key words: Masson pine, Silvicultural technique, Growth of young stand