I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
If the areas are not due to drought, you may be seeing damage from take-all patch or chinch bugs. I suggest you take a sample (4X4" plug from sick, not dead area with some soil and roots placed in ziplock bag) to your County Extension Office and see if they can identify the problem and if necessary prescribe an appropriate remedy.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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