I never cared much for polk at all it has to much of a weedy taste for me.Alot of folks might disagree with me here but I have always felt that eating plants for short term survival is a waste of time.In a stressful survival situation your body is going to require a much higher caloric intake to be beneficial,in other words fish, critters and bugs.Even edible plants can cause diahrrea even if cooked,there are also many poisonous look a likes.Mushrooms have to be identified by an expert and even then they are not always sure,plus mushrooms provide not nutritional content whatsoever.Nuts and berries are the best with juice,sugar and a small amount of fat and protein in the nuts.Almost all grasses are edible but the human body has an impossible taske of digestion,thats why cows have eight stomachs.Stick to the for sures and the basics of plants has always been my logic.