You guys cracked me up with the discussion of the gastric distress some of us experienced in the hunter gatherer class. But the point is a good one. Too many people think having a book about edible plants will save them if they have to find their own food. But even the “safest” foods, like prickly pear cactus, can have nasty consequences if you’re not used to eating nothing but wild foods.
It is also extremely important to be able to identify the plants to NOT eat out there!