Green Deane is my ex. (Yeah, he'll tell you he's a life long bachelor. He'll also tell you to check at least two sources. He's a complicated guy.)
Don't think of eating air potatoes without researching. Probably won't kill you, but could render you infertile. Plus, it's not the bulbils that are eaten. That's all I'm gonna say on that. Way too complicated.
Foragers come into it from all paths. Deane and I both did some as children with parents and grandparents, and both of us planted things, saw how things grew, and watched what animals ate. No, we can't eat what animals eat exactly. Try a mouthful of hay sometime. Deane and I both have, as kids. Neither of us ate pokeweed until we tried it together. Eh, that's not true. He would always let me go first...
Some foragers are armchair only. They know how to set up a deadfall, or why months with Rs in them are bad for oysters, or what parts of thistles can be eaten. They just haven't done it. Even some of the best references out there for edible wild things are written by people who have no first hand experience.
There are a few fora that either specialize in wild edibles or have it as an adjunct. Paleoplanet, ForageAhead for two.
There are several folks on youtube, with Green Deane of eattheweeds the most visible and subscribed. I think his videos are over 170 now. Sunny Savage, Feral Kevin are two others. Steve Brill, Leda Meredith, Sam Thayer, John Kallas are a few other prominent folks but not much on youtube. I think all of them lead teaching tours. Henriette Kress and others have active websites. Lots of blogs out there with people who are knowledgeable about at least a few local wild edibles.
ALWAYS be absolutely certain of your identification before you try eating something. There are two mnemonics to remember for the same key steps: TIME or ITEM. Deane says Identify, Time of year/season, Environment, and Method of preparation. If something you think you've identified is growing in the wrong environment, you are probably wrong. If you pathetically think that we should always eat everything raw: Then I'll see you in the ER, if you make it. Sometimes there are good reasons that highly prized wild edibles are not generally available on the market. Pokeweed being a prime example. I love it, by the way.[/i]