Lawn diseases in McDonough turf such as phythium blight, is an extremely destructive lawn disease caused by the fungus Phythium aphanidermatum.  This type of fungus occurs in all cool season grasses, and though less common it can also affect warm season grasses causing severe and rapid turf damage.  This type of fungus can destroy an infected lawn in as little as a few days.  Phythium blight flourishes in hot and humid weather in temperatures fluctuating between 80 to 95 degrees in areas with little to no air movement but high moisture content.   This type of lawn disease most commonly appears the “150 Rule”.  This is when the day time temperature and the night time temperature is greater than or equivalent to 150 degrees.  When grass blades in the turf stay wet for fourteen hours or more, the phythium blight fungus begins to grow and spread by movement of growing spores by deceased plants, soil movement, surface water and foot travel.  Phythium Blight symptoms begin as small irregular shaped spots ranging from ½ to 4 inches in diameter that join together in larger patches to make long streaks in the turf.   Phythium blight develops in streaks or stripes in the lawn due to the flow of water or drainage of the turf.  During early morning hours during humid weather, you may see a white, mold like growth on the turf known as mycelium.  While the disease if actively growing in the lawn the infected grass blades will appear water drenched, be slippery to the touch, and be brown or black in color.  Once the moisture has evaporated from the turf, the blades will contract up and breakdown causing the turf to appear brown and intertwined.  Phythium blight, one of many Lawn Diseases in McDonough Turf, can survive in the soil for an extended period of time due to past infected plants or fungus spores living in the soil.


Managing Pythium Bligh in your McDonough Lawn

  1. Make sure your turf receives good surface and subsurface drainage
  2. Remove shrubs and tree limbs to increase air flow of the turf and lower chances of fungi growth
  3. Minimize nitrogen applications to cool season grasses during hot and humid periods
  4. Use quality seed
  5. Use fungicides as a preventative treatment  during favoring weather conditions for the fungi to grow and develop