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营造株行距１×１ｍ、１×２ｍ、２．５×３ｍ不同造林密度的白榆试验林，１４年的试验结果表明，３种不同栽植密度对林分的高生长影响不大，但对胸径生长影响非常明显。２．５×３ｍ密度的试验林比１×１ｍ、１×２ｍ密度的胸径生长大３２．０３％和５２．４８％；１×２ｍ密度的比１×１ｍ密度的胸径大１５．４９％。根据树冠与胸径生长的关系推算合理的栽植密度，兼顾用材等经济效益营造白榆成片林，培育８ｃｍ以上的小径材，初植密度每公顷不能大于５０００株；培育１６ｃｍ以上的中径材，初植密度每公顷不能大于１５００株。
The experiment of Ulmus pumila growing at 1 × 1m, 1 × 2m and 2.5 × 3m plantation density for 14 years showed that the three different planting densities had little effect on the height growth of the stand, The effects of growth are obvious. The 2.5 × 3m density experimental forest was 32.03% and 52.48% larger than that of 1 × 1m and 1 × 2m density, respectively. The diameter of 1 × 2m density was 15.49% larger than that of 1 × 1m density. According to the relationship between the crown and DBH growth, calculate the reasonable planting density, take into account the economic benefits of timber and other economic benefits to create a white elm into a piece of forest, cultivate more than 8cm of small diameter wood, planting density can not be greater than 5000 per hectare; cultivate more than 16cm diameter material, Density per hectare can not be greater than 1500 strains.