杨树长截干深栽分阶段作业法造林效果分析

The Advautage of Afforestation with Pollard Poplar Saplings by Staged Operation

杨树栽干苗造林是北方干旱地区主要造林方法之一，采用“长截干分阶段作业法”可真正做到“三埋两踩一提苗”，该法将苗木截干部位从距地表１８ｃｍ提高到３５～３８ｃｍ．挖径、深各６０～７０ｃｍ植苗坑，两次填上踩实分阶段作业，分别验收．该法一般造林成活率达到９８％以上，２～３年树高和胸径分别增加４．２３％和１０．５７％．

Afforestation with Pollard poplar saplings is a good method of afforestation in northemarid regions 'Three-earthing, two-compacting and a single-raising the Sapling' Can be realizedby means of staged operation. The saplings are pokkarded at 35 ￣ 38cm above ground surfacerather than at 18cm The planting hole is 60￣ 70cm in depth and width. Two times ofearthing, compacting and checking can guarantee the survival rate or 98% of afforestion. Thetree height and B H D. are increased by 4.23% and 10.5% respectively in the second or thirdyear,