We cut a 20 acre hay field that has a ton of vetch in it. I can’t remember how it comes back after the first cutting in the early summer. But I do know it is so thick it will make a mess in a hay mower trying to cut. We don’t drill this field with rye in October like the rest, and is always super thick with vetch the next spring without any seeding. I’m pretty sure our crab grass chokes the vetch out after the first time cutting… hope this helps..