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河北杨是西、海、固地区的主要乡土树种。它生长快,树干通直圆满,尖削度小,出材率高,抗病虫害,特别是未发现星天牛危害。河北杨耐早、耐寒、耐瘠薄,故能上山造林。它水平根系发达,根蘖能力强,有“独树成林”的特点,因此,我们于1981～1982年初步摸清了河北杨资源,总结传统的栽培技术,提出发展措施,加速固原地区的林业生产有重要作用。一、在西海固的分布河北杨在固原地区乡村皆有分布,无论是平原、河滩、丘陵、沟壑、沙地及高山坡均有河北杨生长。如固原杨郎乡陶庄三队20年生河北杨树高12.8米,年平均为0.64米,胸径28厘米,年平均为1.4厘米。西吉县西滩村的河滩地也有10余株30年生树高23.5米,胸径32.4厘米,枝下高近占树高的一半,材积0.93立方米。在海拔2050米的西吉县田坪乡燕李村的一阴徒山坡,64年营造河北杨、青杨、小叶杨、旱柳等树种的混交林,82年调
Hebei Yang is the West, sea, solid region of the main native species. It grows fast, straight through the trunk, sharp taper, a high rate of wood, pests and diseases, in particular, has not been found star stellate hazards. Hebei Yang early resistance, cold, barren, so it can be afforestation. Because of its well-developed root system and strong ability of root tillering, it has the characteristic of “single tree forest.” Therefore, we made a preliminary exploration of Hebei Yangyuan from 1981 to 1982, summarized the traditional cultivation techniques, proposed development measures and accelerated the development of the Guyuan area Forestry production has an important role. First, distribution in the West Sea solid Hebei Yang in the Guyuan area are all rural villages, both plains, floodplains, hills, ravines, sand and high mountain slopes are Hebei Yang growth. Such as the Guyang Yang Lang Tao Zhuang three teams of 20-year-old Hebei poplar 12.8 meters high, with an average of 0.64 meters, 28 cm in diameter and an average of 1.4 cm. Xitan Village, Xitian County, there are more than 10 strains of trees 30-year-old tree height of 23.5 meters, diameter 32.4 cm, nearly half of the tree height, the volume of 0.93 cubic meters. In an altitude of 2050 meters Xiping County, Tian Pingxiang Yan Li Village a shade hillside, 64 years to create Hebei Yang, Poplar, Populus, Willow and other tree species mixed forest, 82 years