Answer: I wish I could identify the weed for you but without seeing it, I'd just be guessing. As you've discovered, not all weeds are affected by all weed killers. The weed in your lawn is obviously one of those tough, persistent weeds. I can only suggest that you dig up one of the weeds and take it to your cooperative extension office or well staffed nursery to have it identified and then ask for suggestions about control. Or, you can simply dig the weeds out, roots and all. This should be done before the flowers set seeds and spread them all over your yard. Good luck with your lawn!
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