杨树生长快,经营成本低,轮伐期短,综合利用率高。当前,杨树是国内外营造速生丰产林的重要树种。近年来我区有些林业专业户和重点户为了发展商品经济,不惜占用上等好地栽植杨树,这是很有见识的。这里,根据区内外营造杨树速生丰产林的经验,提出几点需要注意的营造技术问题。一、我区各地生长较好的杨树用材树种有青杨、小叶杨、小美杨(包括合作杨、赤峰杨、通辽杨、白城子杨等)、加拿大杨、箭杆杨和北京杨0567。这些杨树的特性可归结为“四喜”:喜水、喜肥、喜光、喜通风,是强阳性树种。要求造林地水肥充足,土层深厚疏松,易于耕作。土层厚度最好在1.5米以上,地下水位1.5～3米,酸碱度在7左右,含盐量在0.1％以下,有机质为1％左右。理想的造林地块是河淤土、沟谷底部的冲击土,以及土层深厚、水肥条件好的村旁宅旁路旁。造林之前一定要提前一年或两年进行整 Poplar grow fast, low operating costs, short rotation, comprehensive utilization rate. At present, poplar is an important tree species for fast-growing and high-yield forests at home and abroad. In recent years, some forestry households and key households in our district have very good knowledge of the development of commodity economy and are good at planting poplar trees. Here, based on the experience of creating poplar fast-growing and high-yield forests in and out of the area, several technical problems that need to be noticed are put forward. First, growing poplar, poplar, poplar (including Yang, Chifeng Yang, Tongliao Yang, Baicheng Poplar, etc.) poplar, poplar, poplar and Beijing Yang 0567 . The characteristics of these poplar can be attributed to “Si-hi”: hi water, hi fat, hi light, hi ventilation, is strongly positive species. Afforestation requires sufficient water and fertilizer, deep and loose soil, easy farming. The best thickness of the soil layer is more than 1.5 meters, the groundwater level is 1.5 to 3 meters, the pH value is about 7, the salt content is below 0.1% and the organic matter is about 1%. The ideal land for afforestation is river silt, the impact of the bottom of the valley soil, as well as deep soil, water and fertilizer conditions are good next to the village next to the house. Before afforestation must be completed one year earlier or two years