Don't even think about eating them. But in the middle is a large group of plants that, while they may not be generally considered toxic, are not really palatable either. Caragana pods and the fruit of mountain ash and hawthorn are among these. Parts of some plants are toxic, such as the stems of tomato and the leaf blades of rhubarb, but the fruit and petioles of these plants respectively, are delicious. Sometimes cooking or fermentation destroys the toxic principle, as in the case of elderberries.
Some people are allergic to some plants that others find perfectly okay to eat.
Consider the terrible allergic reactions some of us has to peanuts and nuts that others enjoy. So I can't really tell you what to eat. I can only tell you generally what not to eat. And the bottom line is never to eat any plant you cannot positively identify. Get your copy of MontGuide 9902 on poisonous plants in the landscape by writing Extension Publications, Culbertson Hall, Montana State University, Bozeman, MT 59717.