张北县位于河北省西北部,地处内蒙高寒草原南缘。气温低,无霜期短;十年九旱,自然灾害频繁,农业产量低而不稳。解放后,在党的领导下,大力开展林业建设,近几年来林业生产发展很快。但由于地高气寒,树种资源缺乏,在生产中存有一定的盲目性。故出现了造林不见林,见林不成材的问题,给林业生产造成了一定的损失。 为了探求适应坝上地区生长的速生优质树种,尽快实现林木良种化,于1972年从我场引进的179个杨树品种中,选择了15个生长较快、抗性强的品种,营造了杨树品种对比试验林,从中选优,以便推广。 Zhangbei County is located in northwestern Hebei Province, located in the southern edge of alpine steppe in Inner Mongolia. Low temperature, frost-free period is short; nine drought ten years, frequent natural disasters, low and unstable agricultural output. After the liberation, under the leadership of the party, vigorously carry out forestry construction and the forestry production has developed rapidly in recent years. However, due to high altitude, lack of species resources, there is a certain degree of blindness in the production. Therefore, there was no afforestation afforestation, forest afforestation problem, resulting in some loss of forestry production. In order to explore the fast-growing high-quality tree species adapted to the growth in the dam area and realize the forest tree planting as soon as possible, from 1972 poplar varieties introduced in our field in 1972, 15 fast growing and strong resistant varieties were selected to create Yang Comparison of test species of forest trees, from which, in order to promote.