Judy, you get a gold star for going through a whole book on this!
Sounds like it can be a challenge to identify the zone 6/7 winter-hardy edibles. I wonder what the hunter-gatherers did for food in the colder climes before people got the idea of storing food for the winter? Did they live mostly on fish?
Mike, I'd love to hear more about what is motivating you to do all this research! Are you endeavoring to live off the land? Or is this a more theoretical project?
