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 suspect that you are seeing some type of Medic. Broadleaf post emergence products such as Trimec should work on this and any other plant that looks like clover. However when temps rise above about 85 degrees these products can really damage St. Augustine lawns in case that is what you have. You might want to take a weed 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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