Hoof Fungus

(Fomes fomentarius)

Conservation Status

IUCN Red List

not listed

NatureServe

not listed

Minnesota

not listed

 
Hoof Fungus
Photo by Luciearl
 
Description

Hoof Fungus fruiting body (conk) is a 2 to 8 wide, ¾ to 4¾ thick polypore.

The fruiting body is hoof-shaped, rounded and curved downward on top, flat or slightly angled upward below. There is no stalk.

The upper surface is concentrically zoned and hairy when young. The zones are grooved and vary in color in shades of gray and brownish-gray. It soon becomes gray and hairless. The margin is whitish and velvety on actively growing conks.

The underside is whitish. The pore tubes are not layered (stratified).

The flesh is hard and cinnamon brown. When cut in cross section there are no white lines (mycelial threads) visible.

An individual conk can survive for years, even decades, forming a new ridge or furrow each year. It is found on standing or fallen dead trees or on the trunk of a living tree.

 

Similar Species

Willow Bracket (Phellinus igniarius) old conks are black and often cracked above. The margin and undersurface are light brown and velvety on actively growing conks. The pores are stratified. The flesh in cross section shows white mycelial threads.

Habitat and Hosts

Usually birch, but also other hardwoods

Hoof Fungus causes white trunk rot on hardwood trees. It turns the wood into a soft, white, spongy mass.

Ecology

Season

Year-round but grows mostly in early summer and autumn

Use

Season

Another common name for Hoof Fungus is Tinder Polypore, named for its most common usage, as tinder for starting fires. Otzi the Iceman, the 5,000-year-old mummy found in the Alps in 1991, was carrying four pieces of it.

Distribution

Distribution Map

 

Sources

4, 7, 24, 26, 29, 30, 77.

3/22/2025    
     

Occurrence

Very common and widespread

Taxonomy

Kingdom

Fungi (fungi)

Subkingdom

Dikarya

Division

Basidiomycota (club fungi)

Subdivision

Agaricomycotina (jelly fungi, yeasts, and mushrooms)

Class

Agaricomycetes (mushrooms, bracket fungi, puffballs, and allies)

Subclass

Agaricomycetidae

Order

Polyporales (shelf fungi)

Family

Polyporaceae (bracket fungi)

Genus

Fomes

   

Subordinate Taxa

 

   

Synonyms

Agaricus fomentarius

Boletus fomentarius

Boletus ungulatus

Elfvingia fomentaria

Elfvingiella fomentaria

Fomes excavatus

Fomes fomentarius var. leuciticus

Fomes introstuppeus

Fomes inzengae

Fomes mirus

Ochroporus fomentarius

Placodes fomentarius

Polyporus fomentarius

Polyporus introstuppeus

Polyporus inzengae

Polyporus mirus

Polyporus populinus

Pyrenium fomentarium

Pyropolyporus fomentarius

Scindalma fomentarium

Scindalma introstuppeum

Scindalma mirum

Ungularia albescens

Ungularia populina

Ungulina fomentaria

   

Common Names

Hoof Fungus

Tinder Conk

Tinder Fungus

Tinder Polypore

True Tinder Polypore

 

 

 

 

 

 

 

Glossary

Conk

A shelf-like, bracket-shaped fruiting body of certain fungi.

 

Mycelium

The vegetative part of a fungus; consisting of a mass of branching, thread-like hyphae, through which a fungus absorbs nutrients from its environment; and excluding the fruiting, reproductive structure.

 

Polypore

A bracket fungi. A fungi that produces its spores in pores on the underside of a woody fruiting body (conk).

Visitor Photos
 

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Dan W. Andree

Hoof Fungus

Fungi on a dead birch tree...

This was on a dead birch tree along a small creek in rural Norman Co. Mn. 3-18-25. It was on a steep embankment and I couldn’t get the best shot of it but found it interesting how it blend in with the tree etc.

Luciearl

Found on birch snag

Hoof Fungus   Hoof Fungus

Robert Briggs

Hoof Fungus
MinnesotaSeasons.com Photos
Hoof Fungus   Hoof Fungus

 

Camera

Slideshows

Hoof Tinder Bracket Fungus
Andree Reno Sanborn

Hoof Tinder Bracket Fungus
About

Bracket fungus.

Hoof Tinder Fungus

Fomes fomentarius

Fomes fomentarius - fungi kingdom
Fungi Kingdom

About

Published on Jan 23, 2015

Fomes fomentarius - fungi kingdom

 

slideshow

Visitor Videos
 

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Other Videos

Tinder Fungi (Fomes fomentarius) on Birch Tree
Carl Barrentine

About

Published on Jun 3, 2012

Photographed at the Rydell NWR, Minnesota (03 June 2012).

Fomes fomentarius Tonderzwam
Michael Inden

About

Uploaded on Jul 11, 2009

Tonderzwammen op beuk

Fomes fomentarius (Ίσκα)
Kostas Tzouratzoglou

About

Published on May 16, 2015

 

Camcorder

Visitor Sightings
 

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Simply email us at info@MinnesotaSeasons.com.
Be sure to include a location.

Dan W. Andree
3/18/2025

Location: rural Norman Co. Mn.

This was on a dead birch tree along a small creek in rural Norman Co. Mn. 3-18-25. It was on a steep embankment and I couldn’t get the best shot of it but found it interesting how it blend in with the tree etc.

Hoof Fungus
Luciearl
1/15/2020

Location: Cass County

Found on birch snag

Hoof Fungus
Robert Briggs
10/20/2016

Location: Afton State Park, Southern River Trail

Hoof Fungus
MinnesotaSeasons.com Sightings

 

 

Binoculars

 

Created: 10/26/2016

Last Updated:

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