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在日本西部地区的赤松枯死迹地上栽种了侧柏,这种林地土壤条件不好,栽上的侧柏虽然成活了,但是成林后长势较差。可是在这种林地里多处又天然生长出了赤松幼树。如果把这种幼树保留下来,由于赤松比侧柏耐旱性强,对营养的要求不高,因此侧柏和赤松就逐渐混生成双层林。20年后侧柏纯林只长到约7米高,尚未达到郁闭状态,而混交林高20米,完全成林。林龄小时,纯侧柏林和
Platycladus orientalis has been planted on the withered Japanese pine in the western part of Japan, where soil conditions are not good and the cultivated Platycladus orientalis has survived but has not grown well after planting. But in this woodland in many places and natural growth of the saplings young trees. If you keep this sapling, because the red pine than the arborvitae Drought tolerance, the nutrition is not high, so Arborvitae andAdenocephalaA mixed gradually into double forest. 20 years after the Pure Oriental arborvitae grow to only about 7 meters high, has not yet reached the closed state, and mixed forest 20 meters high, completely into a forest. When I was young, pure and sideburum forest