Pests and Diseases Viewer
Caused By:- The Fungi Glomerella miyabeana & Venturia saliciperdaDescription
Willow Blight is actually caused by two diseases, Willow Scab and Black Canker. They are caused by the fungi Glomerella miyabeana(Phyalospora miyabeana and Venturia saliciperda(Fusicladium saliciperdum) that share similar symptoms. Plants that are defoliated year after year and may eventually die. In Spring to Summer when dark spots appear on the leaves which die and remain on the tree. Attack kills the young leaves and causes die-back and eventually cankers of the young shoots and older branches. The fungi overwinters on dead twigs and infect new shoots the following season. Like most fungi wet weather in spring encourages the growth of the fungi. Picture from Wikimedia Commons.
Pruning out diseased shoots and rake up fallen leaves and burn along with spraying with a fungicide that can control the disease will help stop this disease. Avoiding stresses to the tree by providing enough water in dry times will also help. Mulching around the base to the diameter of the outer leaves will help conserve water in dry times, but avoid mulching right up tot he trunk of the tree as this will make ideal conditions for fungi to attack the trunk.