Folklore & Odysseys of Food & Medicinal Plants An Illustrated Sourcebook of Therapeutic Magical Exotic & Nutritional Uses with 200 Illustrations from Ancient Herbals & Old Manuscripts by Ernst & Johanna Lehner. 1973 Softcover Book published by  Farrar Straus Giroux, New York. 

From the Introduction: " Cereal and fruits, salads and vegetables,  beverages and stimulants are the pillars of our daily diet.  When we sit down to breakfast, lunch or dinner or a bracer in between meals, we never fully realize that we are so well supplied with food only because generation after generation of human beings have used themselves as guinea pigs to find out by trial and error which of all the many thousands of plants around the globe were edible.  We forget that at some time, somewhere, everything that covers the earth has been tried for edibility by humans...."   etc

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