Your lawn problems are not clear as to the specific cause. It could be a disease but may also be a varmint making the holes. I suggest you take a sample down to your local Extension Office for identification. Cut a 4 by 4" plug with some roots and soil attached, place it in a plastic bag and seal it up. Take the sample in the zone between healthy and dead turf. Once the pest is properly identified, an appropriate remedy can be made.
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