Some kind of weed that blooms in the Spring before the grass greens up for the lawn mower. One of my sisters remembers that (as children in Kentucky) we used to 'call them' Easter flowers. I don't recall that, but it could be true. Maybe they used to appear around Easter time??? If you have a vivid imagination, you might see an Easter Bunny if you cut off part of the bloom. I think it's a pretty little flower when it's blown up on the computer screen. The blossom is about ½ inch (11-12 mm.) in size.