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2000年以来,随着退耕还林、速生丰产林、杨树新品种推广等国家林业重点工程项目的实施,我省广大平原地区杨树速生丰产林迅猛发展。截止到2009年,累计造林面积达700多万亩,其中栽植杨树新品种107、108杨350多万亩。目前,前期栽植的林分已到达或接近采伐年龄,重新栽植杨树,由于清除伐根、挖坑整地、栽植工费增加、苗木价格提高等因素加大了造林投入,由于当年苗木栽植后的缓苗现象造成树木生长缓慢,延长
Since 2000, with the implementation of key state forestry projects such as returning farmland to forestry, fast-growing and high-yielding forests, popularizing new poplar varieties, the fast-growing and quick-growing poplar in poplar areas in the vast plain of our province has been developing rapidly. As of 2009, a total of more than 700 acres of afforestation area, of which planted new varieties of poplar 107,108 Yang 350 million mu. At present, the pre-planted stands have reached or approached the harvesting age and replant poplar trees. As clearing stumps, digging and site preparation, planting fee increases, price of seedlings and other factors increased afforestation investment, Huanmiao phenomenon caused by slow growth of trees, extended