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窄冠白杨是白杨派种间杂交选育的新品种,是我省农田防护林建设和环境绿化的首推良种。其特性是: 1、速生丰产。一年生苗胸径可达2.5cm,苗高4m,当年即可出圃。二年生大苗平均胸径4cm以上,最大胸径达6～7cm。平均苗高5m以上,最大苗高可达6m以上,苗干笔直,树皮光滑,造林后不缓苗,9年胸径可达30cm,树高20m以上。 2、冠窄根深。树冠呈尖塔形,冠幅小,10年生大树冠幅2.2m左右,仅有一般杨树的1/2～1/3,遮荫面积小;根系深,根幅小,根系呈收拢状斜向生长,主要根系集中在50cm以下,因而不与农作物争水肥争光照,基本不影响农作物产量,是适宜营造农田林网和林粮间作的优良树种。 3、不飞絮不飞粉。窄冠白杨属于雄性优良无性系,春季
Narrow crowned poplar is a new breed of cross between poplar breeding, is our province farmland shelterbelts and greening the most important species. Its characteristics are: 1, fast-growing and high yield. Annual DBH up to 2.5cm, 4m high, that year can be nursery. Born biennial average diameter more than 4cm, the maximum diameter of 6 ~ 7cm. The average seedling height of 5m or more, the maximum seedling height of up to 6m above the stems straight, bark smooth, not Hailing after afforestation, 9 years DBH up to 30cm, tree height 20m above. 2, coronary narrow root deep. The crown is spire-shaped with a small crown. The crown of a 10-year-old tree has a crown of about 2.2 m, only 1/2 to 1/3 of the poplar in general, with a small shaded area. The roots are deep and their roots are small. Growth, the main roots concentrated in the following 50cm, so do not compete with crops competing for fertilizer fertilizer, basically does not affect the crop yield, is suitable for creating farmland forest and forest grain intercropping fine tree species. 3, do not fly Fei Fei. Narrow crown Poplar is a male superior clone, spring