Effects of Pruning Intensity on the Formation and Quality of Clear Wood of Trees in Cunninghamia lanceolata Plantations

【Objective】This study aims to investigate the effects of different pruning intensities on the formation and quality of clear wood of Cunninghamia lanceolata, in order to provide a scientific basis for guiding the cultivation of large-diameter-class,high-quality clear wood of C. lanceolata with reasonable pruning intensity.【Method】With a randomized block design, an experiment was implemented in that a 4-year-old C. lanceolata plantation that was subjected to different pruning intensities（i.e. the trees were pruned annually until their stems with a diameter of 6 cm, 8 cm, 10 cm, and 12 cm, respectively, and the pruning was stopped when the pruning clear bole height of stems reached 7 m, with the unpruned trees served as the control）. After 22 years of pruning, the growth of the trees was investigated. A total of 30 average standard trees from different pruning intensities were selected and cut down, and the stems below 7 m were cut off and carried back to the laboratory for the determination of plumpness of the