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对伊犁地区筛选的4个银×新杨无性系生长特性进行研究。结果表明,银×新杨4个无性系的高生长要早于胸径生长,生长中后期单株之间差异明显;树高连年生长量最大值与平均生长量最大值几乎同步出现,胸径亦如此,树高连年生长量在第4～6年时与平均生长量相交,胸径连年生长量和平均生长量在第6～7年时相交。从18a生的4个无性系生长过程来看,生长可分为3个时期:第0～6年为幼树期,树高、胸径生长比较快。第7～14年为速生期,树高、胸径生长急速上升。第15～18年为近熟期。银×新杨材积的平均生长量与连年生长量在第16年左右时相交,达到数量成熟,此时可进行轮伐。
The growth characteristics of four silver × new poplar clones screened in Ili area were studied. The results showed that the height growth of four clones of silver × xinyang grew earlier than that of the diameter of the breast, and the difference was obvious between the two plants in the middle and late growth period. The maximum value of annual growth in tree height and the maximum value of average growth occurred nearly simultaneously, , Annual growth of tree height in the 4th to 6th year and the average growth rate of intersection, DBH annual growth and average growth in the 6th to 7th year intersection. According to the growth of 4 clones from 18a, the growth can be divided into 3 periods: the 0 ~ 6th year is the sapling stage, and the tree height and DBH grow faster. The seventh to fourteenth years of fast-growing period, tree height, DBH growth rapidly. The first 15 to 18 years of near maturity. The average growth of silver × new Yang volume and annual growth in the first 16 years or so intersection, reaching a certain number of mature, at this time for rotation.