Techniques of Thinning and Pruning in Plantations of Pinus ellottii

Based on the investigation and experimental trials for thinning and pruning on same site,planting densities and stand age,the first time for thinning and pruning of Pinus ellottii plantation was at 7~8 years old.While standard degree of closing of the plantation reached 0.85,current annual increment of DBH started to decline,and the intensity of thinning should not exceed 30%.The second time of thinning should be based on the silvicultural purpose and management intensity,usually intensity of thinning should not exceed 35%,and thinning interval was about 5~6 years.If the culture aims are for the large diameter of construction commercial forest,the third thinning should be carried out,and 600~680 tree/hm~2 should be reserved for harvest.Pruning should be practiced after thinning,and intensity of pruning is 1/3 of tree height for the first time,while 1/2 of tree height is for the second time.The pruning interval is about 3~5 years,and pruning times are the best from early spring to deep autumn.