Pythium Blight
Pythium blight
Photo courtesy of North Carolina State University
Pythium blight is a major disease of both warm and cool season grasses and under the right environmental conditions, can completely devastate a lawn in twenty-four hours.
Signs and Symptoms
Small, blighted spots occur initially. These spots merge forming large, irregular patches. The leaves may be greasy and dark at first, but fade to a light brown color. Under high humidity, leaves become matted and may become covered with white, cobweb-like fungal growth. Borders of affected areas may be black in color. Seedling collapse may occur.
Favorable Conditions:
Poor air circulation, high humidity and temperatures between eighty-five and ninety-five degrees Fahrenheit favor disease occurrence.
Cultural Prevention and Control
Avoid excessive watering during periods of high temperatures to help prevent disease occurance.