So my front yard has turned into a warzone. It's a normal bermuda lawn, inherited from the previous owner. When I first arrived two years ago, there was a little bit of sheep sorrel in one corner. Not knowing what it was, I didn't do anything. This year half the yard is now sheep sorrel, and it's competing with the bermuda to see which is the fastest to invade mulched beds! Both lay deep, fat rhizomes which are not easily extracted, and will advance several feet under very thick mulch. This year my neighbor's Indian / false strawberry is also staging a major invasion, which I have barely under control through manual weeding. I think this fall I'm going to bring out the Round Up for everything that doesn't go dormant in October : )