They are taking over.
White violets can be pulled if they are in flower beds or any weed spray will kill them.
You could spray them with 1/2 warm water, 1/2 vinegar, and an ounce or two of salt per cup of liquid. Shake the mixture up in a spray bottle. Get on your knees and spray the violets where they are thick. The mixture can always kill the grass, too, but killing an invasive wildflower is worth waiting a while on new grass. When new violets start to come back, don’t let them grow until they seed. Pull them up viciously until they are destroyed. Have fun! ☺️
Good luck on removing the white violets! Here are some tips!
Here is another way of looking at violets! They are difficult to erradicate and you don't want to be spraying poisons so learn to appreciate them.
What ? Why would you want to? They are rare and hard to find ! You are blessed with them ! I would love to come get some for my yard and flower beds !
They will turn purple if you make your soil more acidic. I like them.