Buttercup oxalis tends to have a thicker stem, but you'd have to let it grow a little bit to tell. The recent rains have stimulated growth of buttercup oxalis that lay dormant during our dry weather. Good luck getting rid of it. It's an awful invasive weed.

I don't know how to identify them other than by the flowers, but getting rid of them will be a task. I have read that consistent cutting and pulling will eventually exhaust the bulbs and, over the course of several years, reduce or eliminate the presence of buttercup oxalis.

Thank you both for the help. I guess I will need to see whether they throw up the beginnings of a yellow flower before yanking the ones near my Sorrel.

I've spent many hours ferreting out the buttercups from other areas in the yard. At least it's somewhat mind-numbing ....