Research On The Growth And Pulpwood Properties Of Different Provenances Of Larix Olgensis Henry

Larix olgensis. main afforestation tree species of North China, is an important fiber material of pulping and papermaking. This research measures the growth characteristics, fiber morphology and chemical properties of 33 Larix olgensis Henry, from 11 provenances in Maoershan Experimental Forest Farm of northeast forestry university. The results showed:1. The average tree-height, diameter at breast height (DBH), volume and crown width of all provenances show significant differences (P<0.05); the heritability of all growth characteristics is higher than 50%, under above middle-heritability control. The growth of the DBH of Larix olgensis Henry, shows a rapid growth in the juvenile period and a gradual decline after reaching its peak. The fact that the tree-height, DBH, volume and crown width of Xiao beihu and Bai daoshan provenances ranges in the forefront of all comparisons among different provenances indicates that they are the superior provenances in the forestation of this region.2. There are no significant differences between average basic density and latewood percentage of each provenance, and they are faintly effected by genetic control. The average basic density of Tian qiaoling and He long provenances is higher than others. The mean late wood percentage of Bai he, Da hailin and He long is higher.3. Fiber length of He long and Ji xi is longer, the top three ratio of length to width are Da shitou, He long and Bai daoshan. The early wood and late wood fiber morphology of different provenances shows significant differences (P<0.05). The heritability of fiber morphology is higher than 50%, under high levels of heritability control. The average fiber length of each provenances changes similarly with ages, showing the tendency of an annual increase from pith to outside4. The content of holocellulose and pulp yield of different provenances shows significant differences (P<0.1). The content of extract, ash and lignin of provenances shows no significant differences (P>0.05). Holocellulose content and pulp yield of Da hailin provenance ranges the highest; ash content ranges the lowest; the content of lignin and extract is relatively low, Da hailin is the best provenance from the pulpwood of the chemical composition.5. DBH, tree height, volume, basic density, fiber length, ratio of fiber length to height, holocenllulose content, lignin content and benzene-ethanol extractive content are important factors in comprehensive evaluation of evaluating pulpwood. Comprehensive evaluation of coordinate method indicates that Xiao beihu provenance is optimum for pulpwood, in the next place are Bai daoshan and Tian qiaoling provenances.