re: Brown spots in yard

What you have is called brown patch fungus. It is very common in late summer and early fall. Moist conditions combined with less heat and sunshine to keep the soil dry cause it.

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The portions of grass that are brown are dead and wont "turn back to green". A good test would be to pull on the brown blades, if they pull free easily as if rotted off at the base then it is definetly fungus. Treatment is to treat with a fungicide. Granular is preferable, but spray can work. It's not inexpensive.

I live in a wooded area with lots of shade and my St. Augustine gets infected every fall to some degree. I quit trying to fight it. Some areas die but the grass will be brown (dormant) in a month anyway. When the spring time comes around, rake the areas and remove all infected thatch. Then fertilize and the grass will grow back and be healthy and thriving by late April or May.