That's a great idea. I did read that they are very difficult to get rid of and that any small portion left behind is enough to perpetuate the cycle. I know a few did break off rather than pull cleanly and, although I tried to dig the these up, I am certain I missed a few. So, I figure I'll selectively thin next year now that I know what to look for and still have a few blooming. I am surprised how thick these came in given that they are volunteers (or hitchhiked in on something else).
