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 oak trees are the problem it is probably due to roots near the surface that make the soil under the grass not as deep for the grass to root in. Oaks do compete with turf roots but your spots seem to indicate localized problems not something everywhere around the tree. There is little you can do except provide adequate water and fertilizer. You may also want to contact your Harris County Extension Office and see about bringing in a sample for them to look over.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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