Anthracnose (Colletotrichum graminicola), there are two types of anthracnose: basal and foliar. The pattern of symptoms depends largely on weather conditions. Water-soaked stem lesions become dark in color and the leaf blades eventually yellow and die. The central stem can be pulled from the plant quite easily revealing a blackened base. Reddish brown lesions may occur when warm weather, dry soil and increased humidity within the turf canopy occur. Reddish brown irregular patterns on the turf may form as the disease develops. Over time, the patterns turn yellow, tan then brown. Yellowing is stress-related. The fungus, Colletotrichumgraminicola, over-winters on living plant material. Stressed turfgrass, specifically annual bluegrass, bentgrassand ryegrass, are most susceptible to infection. The fungus penetrates the root, crown, and/or leaf tissue during high humidity and wet weather conditions.