针叶树种大苗造林,在园林建设、城市绿化方面已有较长的历史,而用于农田防护林及牧场防护林的营造,仍处于试验阶段。中国科学院林业土壤所研究于1962年在辽宁北部的重风沙地区营造松树试验林带,现已获得良好的防护效果。随后,东北西部地区采用油松、樟子松大苗营造了农田防护林带。近年来,又以大苗移栽的形式扩展樟子松种子林基地,在这些方面均取得了很好效果。可是,造林苗木都是带土坨大苗,这样增加了起苗、包装、运输和植苗的工作量,提高了造林成本,减缓了造林速度,对当前所开展的大规模防护林的营造及绿化工作带来一定困难。如何采用裸根 Coniferous seedlings afforestation, in the garden construction, urban greening has a long history, and for the construction of farmland shelterbelts and pasture shelter, is still in the experimental stage. The Chinese Academy of Forestry Research Institute of forestry and soil in 1962 in Liaoning north of heavy sand area to create pine forest belt, and now has obtained a good protective effect. Subsequently, the northeast of the western region of pine, Pinus sylvestris seedlings to create a farmland shelterbelts. In recent years, seedling transplanting again in the form of expansion Pinus sylvestris seedling base, in these areas have achieved good results. However, afforestation seedlings are Tuo Tuo seedlings, thus increasing the workload of seedling, packaging, transportation and plantation increased afforestation costs and slowed the rate of afforestation on the current large-scale shelterbelt development and afforestation work with To some difficulty. How to use bare root