毛白杨是我省的乡土树种,除北部高寒地区外,广大的平原、山区沟谷均有分布。它生长快、材质好,很受群众喜爱,是“四旁”绿化的主要树种之一。但是有些地方,定植后头几年生长缓慢,树干弯曲,侧枝下垂,叶片狭小稀疏,皮色黑灰,且易遭受病虫害,致使毛白杨幼树生长极不正常。经过二、三年后,根系逐渐发达,皮色转绿,叶片变大变厚,顶梢明显抽出,才恢复正常生长。这种现象,统称为毛白杨的缓苗现象。根据我省各地试验,这是可以克服的,主要措施是: Populus tomentosa is a native tree species in our province, in addition to the northern alpine region, the vast plains, mountain valleys are distributed. It grows fast, the material is good, is popular the masses favorite, is “all around” one of the main tree species. However, in some areas, the first few years after planting are slow to grow, the trunk is bent, the branches are drooping, the leaves are sparsely populated, the skin is dark gray and susceptible to pests and diseases, resulting in extremely abnormal growth of poplar young trees. After two or three years, the root system developed gradually, the skin color turned green, the leaf became bigger and thicker, the top tip was obviously extracted, and the normal growth was restored. This phenomenon, collectively referred to as white poplar Huanmiao phenomenon. According to the test across the province, this can be overcome, the main measures are: