杨树烂皮病为害杨属各个种,分布普遍。是苗圃和幼林的重要病害之一,也是成年树枝枯的主要原因。我国杨树烂皮病病原菌过去的报导是Valsa sordida Nit.北京地区引起杨树烂皮和枝枯的病原菌,除Cytos- Poplar bad disease Yang is all kinds of species, distribution is widespread. Nursery and young forest is one of the major diseases, but also the main reason for the adult branch withered. In our country, the pathogen of the disease of rotted bark of poplar was Valsa sordida Nit.