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杨树速生丰产林常受腐烂病(也叫烂皮病)危害,病斑常见于主干、大枝及树干分岔处。初期出现暗褐色水浸状病斑,皮层组织腐烂变软,用手压有水渗出,以后病斑失水,树皮下陷,有时龟裂,病斑上长出许多针头状小突起,病部皮层腐烂,易剥离。当病斑环绕一周时,病部以上的枝干随即枯死。病菌是一种寄生性很弱的真菌,它常通过冻伤、虫伤、日灼伤等伤口侵入树体而发病。多侵染3～10年生树木。这种病4～5月份发病,7月份为发病盛期。对于这种杨柳树木的毁灭性病害,可采取以下措施防治:
Poplar fast growing forest often rot disease (also known as bad skin disease), lesions common in the trunk, branches and trunk bifurcation. Dark brown early spot-like lesions, cortical tissue softening, excretion of water pressure by hand, later water loss of the lesion, bark subsidence, sometimes cracking, lesions grow many needle-like protrusions, disease Department of decay, easy to peel. When the lesion surrounds a week, the branches above the diseased part die immediately. Pathogenic bacteria is a very parasitic fungus, it often through frostbite, insect pests, burns and other wounds invade the tree and disease. More infested 3 to 10 years old trees. The disease 4 to 5 months of onset, the peak incidence in July. For the devastating diseases of this willow tree, the following measures can be taken to prevent and control: