This plant disease is caused by a fungus (Elsinoe ampelina) that may do considerable damage a few years in a row, and then disappear. It is often called birds-eye rot because of the similarity of the spots on the fruit to a bird's eye. It is seldom severe on Concord or muscadine grape vines. The disease first attacks the new growth. The spots on the stems often merge, girdling the stem and killing the vine tips. Anthracnose is prevalent during wet periods in the spring and in poorly maintained vineyards. The fungus survives the winter on old lesions on the canes. Although this disease doesn't kill the grape vines, the infected fruit are often misshapen and unappetizing. Several years of attack from anthracnose sufficiently weakens the vines to make them more susceptible to other problems.
Discard infected fruit, and prune out diseased canes. Sprays applied after spotting occurs are ineffective. Next spring, before the buds open, spray the vines with a fungicide containing lime-sulfur. Treat the plants with a fungicide containing ferbam when the shoots are 1 to 2 inches long, when they are 6 to 10 inches long, just before bloom, just after the blossoms fall, and 2 to 3 more times at intervals of 2 weeks. Spray all canes and leaves thoroughly.
Plant Care for Grapes