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!
I doubt it is grubs that are turning your grass brown. It may be a disease or damage from a weed and feed fertilizer or another type of weed killer. I suggest you take a sample 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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