Unless they have taken over your lawn, I think using an herbicide is a bit of overkill :-) Herbicides that would be effective on the violets also have the potential to damage or kill any desired plants in the area unless you are very careful with the application. As much of a time consuming, labor intensive process as it may be, I would still lean to to pulling/manual removal for any planting beds. Or tolerance :-)

For lawn areas, Bayer Advanced Lawn Weed and Crabgrass Killer is registered to control wild violet. Also, the attached link may be helpful.

Why is this cute native plant causing so much dislike & distress? (Usually called V. sororia. You may find more info using that name in a search.)

I appreciate the follow up from everybody. Thank you very much. The cute native plant looks wonderful anyplace but invading my lawn. This is why I would like to get rid of it

We have this growing along our fence as the neighbor likes it I guess, but I spray with weed be gone early in spring when it 1st pops up and just lately noticed it coming back in August, but will wait until Spring again to spray unless it gets too thick.

Use ortho oxalis and clover killer with triclopyr. I mix in a little dawn dish soap to help stick it to the weed and break down the wax on the leaves. Two applications will do the trick

They are adorable dainty little plants, and they are wildly invasive in my yard. I saw them a couple years ago, and now I am pulling them up constantly, and my grass is being overtaken. So although they are cute, I have been tending my gardens and my lawn for decades and they are not part of the design.

Thank you Greendave!