There could be several problems listed below are out top five reasons.
1. Could be an animal eliminating themselves in the same spot (often the urine of female dogs or cats are more of a “toxic” problem).
2. Brown Patch is a fungus that affects Bermudagrass and St. Augustinegrass. You will see circular brown areas in the lawn. The areas will develop during cool, wet weather, usually in the spring or fall. The leaves of the turfgrass will wilt and die, which will cause brown patchy areas.
Control: Terraclor (PCNB)*
3. Take-all Patch (Bermuda decline). Outer edge of irregular patch is chlorotic to straw-colored; grass within the patch is straw-colored and “crisp”; leaves not easily pulled from the stolon.
Control: About the best control is the same as for brown patch and use the highest amount recommended
4. Spring Dead Spot causes dead spots to appear in Bermudagrass during the spring. It usually occurs in lawns that are at least 3 to 5 years old.
Controls: Aerating the soil core should reduce thatch. Fungicides may be able to be used to control spring dead spot.*
5. Gas, oil, fertilizer spill etc. Grass leaves rolled; bleached or brown grass in spots or streaks.
*Indicates these can be found in the real dirt A Gardening Handbook for Parker County