Dandelions and their cousins are the "gateway drug" to serious foraging. They grow in nearly everyone's lawn, and most people know what they look like and that they can be eaten. Picked young, they are great in salads, and by midspring they become a stewing green par excellence.
I include chicories and wild lettuces here because they are all similar in the kitchen and tend to grow next to each other. I've picked a dandelion, a prickly lettuce, and a young chicory side-by-side-by- side more than once.
One of the best parts about picking these plants is that in cool weather, finding them is merely a matter of venturing out into your yard. It can be cold, but the sun is shining long enough that many wild plants are still doing their thing. The ideal time to collect yard greens is after cool rains followed by some sunshine. Nights should still be nippy, and days not above 70°F.
The simplest, best way I like to eat wild greens is to wash them well, get a few tablespoons of olive oil hot in a large saute pan, then cook them while they are still wet, which helps them wilt fast with the resulting steam. Add salt as soon as they wilt, maybe some minced garlic, maybe some chile pepper, definitely black pepper--and a squeeze of lemon or lime right when you serve them. This method is simplicity itself, takes less than 5 minutes, and keeps most of the nutrients in the greens. The recipe I feature in my book showcases their beauty and flavor even further.
Try the author's recipe for Wild Greens Risotto.
When in Doubt, Check It Out
Never eat something you cannot positively identify. There are not a lot of poisonous lookalikes when searching for wild greens (in my upcoming book, I discuss pokeweed as an example), but better safe than sorry.
Hunt, Gather, Cook: Finding the Forgotten Feast (Rodale Books, summer 2011) is not meant to be a full-on guide, so I recommend Peterson Field Guides, Audubon books, and regional books. I have a collection of them for reference, and I also carry a couple (an Audubon and a Peterson) in my backpack when I am out and about. --H.S.