Mushrooms are the fruiting body of a fungus. There are thousands of species, some of which are edible. Many are colorful, funky or mystical. Excellent guides to the worlds of fungi include Mycelium Running by Paul Stamets, Mushrooms of the Redwood Coast by Siegal and Schwarz and Mushrooms of the Pacific Northwest by Trudell and Ammirati.
Many areas have local mushroom clubs or mycological societies. Click the buttons for links.