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!
Where the nimblewill came from I cannot know. It is not easy to control because there are not any product that are selective for nimblewill in a lawn. The standard recommendation is to hand pull and/or use a non selective product such as glyphosate (Roundup, Kleenup, etc.). Try to get the product on the weed but minimize contact with the turfgrass because it will be killed too. Give it a couple of weeks to work and then if you like you can plug fresh sod back into the dead areas.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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