横山县地处陕北长城沿线,属毛乌素沙漠的东南缘。境内榆定公路以西和北属风沙区,以东和南属黄土丘陵沟壑区,风沙危害和水土流失严重。解放后,横山县积极响应毛主席“绿化祖国”的伟大号召,大搞植树造林,绿化荒沙荒坡,特别是无产阶级文化大革命以来,社队集体有计划、有组织地营造以柠条为主的防风固沙林和水土保持林。截止1975年底全县种植柠条45万亩,约占全县林地总面积的百分之五十,对防风固沙,控制水土流失,促进农牧业生产起了一定的作用。近十几 Hengshan County is located along the Great Wall of Northern Shaanxi, belonging to the southeastern margin of the Mu Us Desert. In the west of the territory of Yuding Highway and north of the wind and sand area, to the east and south are loess hills and gully areas, the risk of sand damage and soil erosion is serious. After the liberation, Yokoyama Prefecture responded positively to the great call of Chairman Mao for “greening the motherland” and vigorously engaged in afforestation and afforestation, especially since the Great Proletarian Cultural Revolution. Windbreaks and soil conservation forests. By the end of 1975, 450,000 hectares of Caragana were planted in the county, accounting for about 50% of the total area of ​​forest land in the whole county, playing a certain role in windbreak and sand fixation, controlling soil and water loss and promoting the production of agriculture and animal husbandry. Nearly a dozen