September is a great time to focus on fungi because recent rains have created perfect
conditions for mushrooms to emerge. It’s also National Mushroom Month!
With names like Dead-man’s Fingers, Elegant Stinkhorn, Poison Pie, Elf Cup, Witch’s Butter and Angel Wings, mushrooms conjure up a wide variety of feelings and images. Children’s tales illustrate them as stools for toads or umbrellas for pixies. Horror stories utilize poisonous mushrooms as murder weapons. Many people enjoy them on pizza. A few species cause hallucinogenic effects.
These varied ideas have their basis in biology. Unlocking mushroom mysteries can enhance our appreciation of them.
Mushrooms and their relatives are in the biological kingdom Fungi. Common characteristics include having no means of independent locomotion and acquiring nutrients via absorption. Fungi were once lumped in the same kingdom with plants, but unlike green plants which through photosynthesis use the sun’s energy, water and carbon dioxide to produce sugars (food for themselves and animals), fungi are saprophytes — living off decaying organisms.
Mushrooms are the fruiting bodies which produce spores for reproduction. They can be shaped like coral, horse hooves, balls or the familiar cap on a stem. The bulk of the organism lives hidden underground or buried in wood until conditions are ideal for the “fruit” to arise, ripen and disperse its spores.
An example of this process occurs with the globular “puff ball” fungus. Many species of puff balls emerge in lawns, parks and open woods. Most are stalkless, resting loosely on the ground appearing like a golf ball, softball or, in the case of the Giant Puffball, like a soccer ball. When they first pop out, they are usually white and solid, yet soft. As they age over the course of a few days, the spore mass, comprised of millions or trillions of microscopic reproductive bodies, will change to yellowish, greenish-brown or purple. Some species develop a small hole in the top which releases the spores like smoke from a chimney, hence the name puff ball. Other varieties release the spores as the walls of the ball disintegrate into a pile of colored “dust.”
Spores travel on the wind. If they land in a place that is conducive to germination, they develop thread-like strands called hyphae. As hyphae branch and fuse together, they form an underground network called mycelium, the vegetative portion of the fungus which absorbs nutrients. When favorable conditions occur the mycelium begins to form tissue that grows into the immature fruiting bodies. As those bodies develop, they push through the substrate and appear as mushrooms which grow spores to start the cycle all over again.
Mushrooms such as puff balls have a relatively short fruiting cycle, like an annual plant — flowering and creating seeds in just one season. “Shelf fungus,” in the Polypore family are more like perennial plants. Spores are produced in tube-like structures on the underside of the cap. These caps may be fleshy or woody and often persist on the side of a tree or on buried wood for years. When conditions allow, the cap produces new tubes, adding to the size of the “shelf.” Turkey-tail, Birch Polypore and Artist’s Conk are common examples of this type of mushroom.
Some mushrooms have stalks and a cap with gills on the underside. The pattern and placement of the gills can help with identification. Spores are produced in the gills and drop out when they are mature. Collecting the spores on paper to create a spore print is also a trick for determining the species.
Color can also be an identifying trait. Many mushrooms are brown or tan, like dried leaves, or white to resemble dappled sunlight. Yet others are bright yellow, orange, red or purple. In some cases, as with various insects, the bright color may indicate a level of toxicity that warns, “don’t eat me!” Unfortunately, it’s not that easy to distinguish poisonous mushrooms from those that are delicious. The best way to learn which are safe and which aren’t is to go mushrooming with an expert.
I’m content to just admire how the mushrooms augment the fields and forest, knowing that they are doing an important job of recycling nutrients and adding a bit of mystique to the landscape.