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白榆,亦称榆树或家榆。白榆生长快、材质好、用途广、适应性强,目前已成为我国北方各省(区)重要的造林树种,我区许多林业专业户对白榆很感兴趣。白榆是一个明显的多型种,在形态、生理、生态等方面都有较多的变化,因此出现了一些优良类型。所谓优良类型,是指白榆的株型主干高大,通直圆满,侧枝细,分枝角度合理,冠幅窄,适于密植,单位面积上出材量高。这样的白榆有钻天白榆、细皮白榆、粗皮白榆和密枝白榆。钻天白榆在山东、河北、河南等省均有分
Elm, also known as elm or elm. White elm grow fast, good material, wide use, adaptability, has become an important afforestation species in the northern provinces (autonomous regions), many of our area forestry professionals are very interested in the elm. Ulmus is an obvious multi-species, in terms of morphology, physiology, ecology, etc. have more changes, so there are some good types. The so-called fine type, refers to the tall elm plant trunk tall, straight straight round, fine side branches, branches angle is reasonable, the narrow width of the crown, suitable for close planting, the unit area of a high amount of wood. This white elm drilling days elm, fine white elm, bark elm and dense branches elm. Drill the day and the elm in Shandong, Hebei, Henan and other provinces have points