Dead fingers are the scariest mushrooms in the forest

The best Halloween decorations sometimes come straight from nature. Intricate spider webs, giant pumpkins and a mushroom that could make you stop in your tracks. Commonly referred to as the Finger of Death, Xylaria polymorpha can look like rotting zombie fingers. This and other similarly scary looking mushrooms of the genus XSubscribe can be found throughout the United States.

“It might give the false impression that a dead body is emerging from the foliage, but this Xylaria Mushrooms are associated with wood,” says mycologist Matt Kasson of West Virginia University Popular Science“They are saprophytes, which means they feed on dead material. And this dead material, this substrate, happens to be wood.”

Dead man's fingers are usually seen at the base of rotting or dead trees, where they decompose the dead wood and release nutrients into the soil for new plants to grow. The black, finger-like shapes themselves are the sexual reproductive structures of the fungus. Sexual spores are produced in tiny bottle-like structures in each finger.

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“Think about the pores of our skin and blackheads. When we squeeze a blackhead, what's left is basically this secreted lump,” says Kasson. “It's similar to a dead person's fingers. All that black tissue is lined with these bulbous fruiting bodies called paresthesias.”

Xylaria are incredibly opportunistic and can release these spores for several months or even years. The structures also have a very stiff exterior, similar to a real finger. While other fungi like button mushrooms are more volatile and fall over, Xylaria Their strength allows them to continue releasing spores and increase their chances of reproducing. They can also form thin, thread-like structures called hyphae, which grow through the dead or dying wood rather than protruding from the trunk of a tree.

Some species are known to cause black root rot, but this is usually a problem in trees or shrubs that are already stressed. According to the University of Wisconsin-Madison, this disease occurs in trees such as apple, crabapple, pear, cherry, plum, American elm, Norway maple and honey locust.

“Many fungi simply take advantage of plants that are already weakened and stressed. That is, they may have been stressed by drought or had a predisposition to senescence, that is, they were simply very old and at the end of their life,” says Kasson. “So there are many fungi that look like the fingers of a dead person.”

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As with zombies themselves, it is important to remember that the finger is just the tip of the iceberg and will continue to grow under the right conditions. Honey fungus ostoye– also known as the giant mushroom – is considered the largest living organism in the world. The giant mushroom in eastern Oregon covers more than 3 square miles and is estimated to be between 1,900 and 8,650 years old, so simply pulling a dead person's finger off the trunk of a tree won't get rid of the mushroom itself.

“Mushrooms are immortal in a sense,” says Kasson. “If they're at the base of a single tree, that tree will eventually run out of resources. But if it's a whole forest of trees that can spread through spores, it can go on forever.”