Susceptible species and favorable conditions
Susceptible species: All cool-season grasses and Bermuda grass. Bentgrass, annual bluegrass, tall fescue, and perennial ryegrass have greater susceptibility.
Favorable conditions: Pythium blight can become quickly established during hot (80°-95°F), very humid weather. It can sometimes also occur at lower temperatures during cool, wet weather. It is one of the worst turf diseases, and can kill a plant in 24 hours in ideal conditions.
Recommended cultural practices
- Avoid overwatering, and don’t water late in the day during periods of hot and humid weather.
- Ensure adequate drainage.
- Avoid mowing wet lawns.
- Avoid excessive rates of nitrogen fertilization to prevent lush growth, which is very susceptible to Pythium blight.
- Aerate to reduce thatch levels and relieve soil compaction.
- Mow high
Chemical control: Multiple applications of fungicides as part of a preventative treatment program may be warranted to avoid spread of pythium blight.
Photo credit: Lee Miller, University of Missouri, Bugwood.org