PHOTO: © Neil Soderstrom
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Anthracnose
IDENTIFICATION — When anthracnose strikes after a cool, wet spring, you’ll find irregular dark blotches on leaves. Sometimes buds or small twigs will also be infected — symptoms vary with the host plant. Infected parts, especially leaves, eventually drop off.
DAMAGE — Anthracnose, caused by several types of fungi, attacks mainly shade trees, such as sycamore, ash and maple; also some small ornamental trees, like the dogwood in this photo. Spores overwinter on twigs, move through the air and begin to grow in cool, wet weather. Anthracnose rarely kills the tree, but repeated defoliation weakens the plant and makes it unsightly.
PREVENTION — Plant trees in sites with good air circulation and prune dense growth to improve air movement. Keep trees fertilized and vigorous so they can grow new foliage quickly. When choosing a new tree, read tags or ask for resistant cultivars.
