Mushrooms are fungi with numerous species growing naturally throughout North America -- more than 2,000 in the state of Ohio alone. All mushrooms have a cellular structure and reproduce by spores, but otherwise they are so varied in size, shape, color and other physical characteristics that it takes an expert to identify them accurately. The most common division is between edible and non-edible mushrooms.
Many mushrooms have an above-ground part, called a fruiting body, to distribute their spores. If this part has a cap (a wide top) and a stem (a stalk growing out of the ground), it has what is commonly called a mushroom or toadstool shape. Other mushrooms can be fuzzy, frilly, shaggy, cupped or shelf-like.
Color
Mushrooms come in many colors from white to black, including purple, yellow and bright red, but most are some shade of brown or beige. The commercially raised mushrooms in supermarkets tend to be white varieties. Red mushrooms may be edible, but red is frequently a warning color in nature and there are so many edible mushrooms in other colors that the safe bet is to avoid eating these on general principles.
Collecting
Hunting wild mushrooms is a common hobby and some collectors become very knowledgeable and adept at gathering many varieties of edible mushrooms. A field guide to edible mushrooms with accurate photographs is essential and hunting with an expert while learning is highly recommended.
Poisoning
Some people call a non-edible mushroom a toadstool, but it's just a mushroom. Some mushrooms are mildly toxic and will cause only digestive upset. Others are hallucinogenic. Still others, will cause humans to die in a very unpleasant fashion. These non-edible varieties are sometimes almost indistinguishable from the edible. There is no rule of thumb for the untrained mushroom hunter to distinguish these from edible mushrooms: not color, shape, smell, taste or any other physical characteristic. There is no touchstone, such as garlic or silver. Animals can eat mushrooms that will sicken or kill a human. Peeling will not remove the toxins, nor will cooking. Books have been written on the subject of mushroom poisoning, but basic first aid consists of going immediately to the nearest hospital, preferably one with a poison control center, taking all the suspect mushrooms in any form (raw, cooked or vomited) for laboratory analysis
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Structure