在“三北”防护林第一期工程建设中,风沙干旱地区营造农田防护林,同样立地条件下,同样进行整地,栽植同样树种,由于采用大苗、根桩苗等不同类型苗木,其效果是不同的。 据昌图县三江口乡调查。栽植杨树根桩苗,平均成活率达97％;适时进行除草、松土、抹芽、定干,当年高生长达1.5米以上,一次造林一次成型。而栽植二年生杨大苗, In the construction of the first phase of the “Three Norths” shelterbelt, farmland shelter belts are to be constructed in arid and sandstorm areas. Under the same site conditions, the same site preparation and planting of the same tree species will result in different effects due to the use of different types of seedlings such as large seedling and root pile seedlings . According to Changtu County Sanjiangkou survey. Planting poplar root pile seedlings, the average survival rate of 97%; timely weeding, loosening, wiping buds, set dry, when the high growth of 1.5 meters or more, an afforestation a molding. The planted biennial Yang Miao,