lawn weeds are described as trendy food by the Wall Street Journal (http://online.wsj.com/article/SB124338226000356493.html
Tcamp shared this with me - I stopped my WSJ subscription a couple of years ago. I'm not really craving greens right now, with a garden full of planted ones and a fridge full of CSA greens from a friend on vacation. But the nice thing about those lawn weeds is that they will be there all year, even when my garden lettuce has gone leggy and bitter, and many of them even in winter. Food just doesn't get any more local than the front lawn.
And plus, that's the only kind of leafy greens my kids will eat and consider it fun. They don't get enough to count for a daily vegetable, but at least they'll try them without a fight!
Count me out on the pokeweed, though. I think that if you have to change the cooking water, the plant's secondary chemistry might be just a little to challenging for my system. I'll let it grow, and if someone needs if for the food bank it will be there.