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一、退化小红柳林及其形成的原因退化了的小红柳(S.mirostachgaTurcge)林在浑善达克沙地很普遍,约占整个沙地面积的80%左右。其特点是树丛低矮,一般高130—180厘米,枝条长势衰退,年生长在10厘米以下。由于经常选割,通直的单株尽皆被割掉,留下干形弯曲的单株,直到衰老死亡,形成每丛小红柳都有一年生至多年生的单株。长势衰弱的老株常遭到吉丁虫、芳香木蠢蛾、杨透翅蛾等蛀干害虫的危害。枝干、根部蛀孔纵横,被害株体
First, the degradation of small red willow forest and the reasons for the formation Degraded red willow (S.mirostachga Turcge) forest in Hunshandake sand is very common, accounting for about 80% of the entire sand area. It is characterized by low trees, generally 130-180 cm high, branches decline, the annual growth of 10 cm below. Due to the frequent cutting, the straight plants are cut away from each other, leaving a dry, curved plant until the death of aging, resulting in the formation of an individual from annual to perennial in each cluster of red willow. Elder growing strains often suffer from jejuni, aromatic wood moths, poplar moths and other bore harm pests. Branch stems, vertical and horizontal root hole, the victim body