Hello Raymond,

Thank you for your question.

Brown patch disease is caused by a fungus and generally affects the grass blades and the tillers (spreading mechanisms) but does not damage the crown of the grass plant. Once the conditions for fungus growth are no longer optimal, the grass plants will regrow, but the affected area is left thin and sparse.

Here is a good article about patch diseases. Homeowner action is summarized at the end of the article. https://www.extension.purdue.edu/extmedia/bp/bp-106-w.pdf

The best solutions for brown patch are cultural: avoid nitrogen fertilizer during the hot summer months, and do not water late in the day. Water early enough that the grass plants are dry before darkness. Fungicide applications by homeowners are not recommended for brown patch infections. If you are determined to apply fungicides, you would be best off contacting a certified commercial applicator.

Dr. Kevin Frank from MSU offered the following statement about brown patch in this week’s Landscape Team Alerts. A short term cool-down in Michigan will stop the spread of Patch disease because conditions are becoming unfavorable for it.

“Dollar spot and red thread have been popping up on lawns. With the high temps might see some brown patch in some lawns but it won’t persist with cooler temps ahead.”

Hope this helps.