Leaf infection appears as tiny, reddish-brown spots on the upper surface in early June. The lesions enlarge to one-forth inch or more in diameter and become brown with black borders. A ring of black fungus bodies develops near the outer edge of the brown area. Lesions on stems and tendrils are longer and blacker than those on leaves. Stem lesions are narrow, sunken and often split lengthwise on the vine.
Infections begin to appear on the fruit when the grapes are about half grown.
At first, a small, white spot forms. It enlarges rapidly until the entire grape is rotten. Affected grapes soon turn black, shrivel and dry up. Minute, black fungus fruiting bodies develop on the surface of the dried fruit. Grape Anthracnose Anthracnose may cause extensive losses in poorly kept Georgia vineyards, but it can be controlled economically.