biodiversity homepage
click for contacts  

Photo by: Vic Medland

Location:, Green Bay, WI

Date taken:12 June 2002

Dead Man's Fingers.

Dead Man's Fingers (Xylaria polymorpha)

The clustered blackened fruiting bodies of Xylaria polymorpha rising up from the ground really do look like the fingers of a dead corpse reaching up from the grave. This distinctive fungus grows 5 to 8 cm tall and is commonly found near living and decaying trees and roots. However, it is often overlooked because it blends in with the decaying wood it grows from.

Dead Man's Fingers are Ascomycetes (fungi in the division Ascomycotina). Reproductive spores are located in tiny tube shaped cells called asci that are clustered inside tiny cup-like structures called perithecia. The perithecia are visible as tiny black dots embedded in the white stroma or structural material of the mushroom. This species is long lived and releases spores over several months. The fruiting bodies mature between June and October, but can last into the winter and sometimes several years. There are over 2000 species of Ascomycotina, many of which are important to humans. Morels and truffles, as well as the species that cause Chestnut Blight and Dutch Elm disease are in this group. Xylaria polymorpha is a fungus that that feeds on live wood and causes soft rot in tree roots. The hyphae (thread-like underground structure of the fungus) release enzymes that digest glue-like chemicals called glucans that hold the woody cells of the trunk or roots together. As the fungus feeds the cells literally separate from each other and the structure collapses. Unfortunately for us, this mushroom was photographed in our tree-filled yard. But usually they are found in woods and forests and they are not typically considered a pest species like some other Ascomycetes.

Contributed by Vicki Medland, Cofrin Center for Biodiversity

Sources and Further Information:

For more information about and great photos of this fungus and many others visit UW-LaCrosse professor Tom Volk's Fungus web pages at:

Moore-Landecker, E. 1982. Fundamentals of the Fungi. Prentice Hall, Inc.

© 2001-2004 The Cofrin Center for Biodiversity and the University of Wisconsin Green Bay, All Rights Reserved
Last updated on April 15, 2014