Need help to identify this garden weed.
The weed your describing is a aster, very tough to control. The best way is through a pre-emergent process of applying a minimum of two x a year. If its really bad you can grasp it carefully and pull it up as it has one long tap root. The other alternative is applying a post emergent chemical on it that is labeled for ground aster? There are several different ones out there depending on where you shop. Be sure its also labeled for the type of turfgrass you have as well?
P.s. I go out and pull mine when I have time, just set and listen to music as I pull? Be sure and remove it and put it in the compost or a lawn bag.