When it first appears above ground in the spring, the club/finger-shaped fruit of Dead Man’s Fingers (Xylaria polymorpha) appears powdery white from the asexual spores that cover its surface. As it matures, it acquires a crusty, black surface. This is the sexual stage. The interior of the fruiting body of this fungus is white; just inside the outer surface is a blackened, dotted layer containing structures called perithecia which hold sacs of sexual spores. Dead Man’s Fingers, unlike most fungi (which release their spores in a few hours or days) releases its spores over months or even years. It can have many separate “fingers” and sometimes the fingers are fused, causing it to look somewhat like a hand. Look for this fungus growing on hardwood stumps and logs, particularly American beech and maples.
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Typically you find this fungus growing from the base of a rotting stump, poking up through the ground like a dead man’s fingers — hence, the name. The “fingers”, or fruiting bodies, can take many forms, including individual fingers or fused fingers that resemble a hand. It’s thought that Dead Man’s Fingers, Xylaria polymorpha, is actually several species of fungi, which have yet to be identified. In the spring, this fungus is covered with light-colored, asexual spores, which give it a grayish tint. As it matures, it darkens with the production of mature spores, eventually turning black. Most fungi disperse their spores over a period of a few hours or days. Dead Man’s Fingers is much slower, releasing its spores over many months or even years. (Thanks to Marian and Charles Marrin for photo op.)
Dead Man’s Fingers (Xylaria polymorpha) is a fungus that can be found growing from the bases of rotting stumps, and gets its common name from the way its fruiting body pokes up through the ground like a dead man’s fingers. “Xylaria” refers to growing on wood and “polymorpha” means many forms. This species has a very variable fruiting body, sometimes with many separate “fingers” and sometimes with the fingers fused into something more like a hand.