TL;DR
Brown patch is a fungal lawn disease caused by Rhizoctonia solani that scalds out roughly circular straw-colored areas from inches to several feet across, often with a darker smoke ring at the margin in morning dew. It strikes cool-season grasses, tall fescue and ryegrass especially, during hot humid nights above about 68 F, and thrives on excess nitrogen and evening watering that leaves blades wet overnight.
What it means
Brown patch is a fungal lawn disease caused by Rhizoctonia solani that scalds out roughly circular straw-colored areas from inches to several feet across, often with a darker smoke ring at the margin in morning dew. It strikes cool-season grasses, tall fescue and ryegrass especially, during hot humid nights above about 68 F, and thrives on excess nitrogen and evening watering that leaves blades wet overnight. Cultural correction, watering early morning only, easing summer fertilization, improving airflow, does most of the work, with fungicides such as azoxystrobin reserved for active outbreaks. Damaged crowns usually survive, so most lawns refill as weather cools.
Where it sits in the glossary
Brown patch is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
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See also
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