Aspen Bracket

(Phellinus tremulae)

Conservation Status
Aspen Bracket
Photo by Luciearl
  IUCN Red List

not listed

 
  NatureServe

NNR - Unranked

 
  Minnesota

not listed

 
           
           
           
           
 
Description
 
 

Aspen Bracket is a common, easily recognized, hoof fungus. It occurs in Europe, Asia, and North America. In the United States it occurs in the east from Maine to Massachusetts, west to Minnesota and Iowa. In the west it occurs from the Rocky Mountains to the West Coast. There are only a few records from the Great Plains and the southeast. It also occurs across southern Canada. It is common in Minnesota. It grows only on quaking aspen and bigtooth aspen, and it is the only hoof fungus found on those trees. It causes white trunk rot, turning the wood into a soft, white, spongy mass.

The fruiting body (conk) begins in a large, horizontal, pore-like opening (lenticel) in young bark. When it first appears, it is convex and semi-circular or fan-shaped. The upper surface is brown to dark brown, paler toward the edges, and is covered with fine hairs. As it ages it expands, darkens, and cracks. The mature conk is 1½ to 8 (4 to 20 cm) long, ¾ to 4¾ (2 to 12 cm) thick, and variable in shape. It is usually hoof-like. As the tree grows, the top of the bracket is pulled upward while the lowest part remains firmly attached. The upper crust is sloped upward, crescent-like, while the lower side (pore surface) remains flat or is slightly angled. The upper surface is hairless, gray or dark gray, and usually faintly zoned. The older conk is blackish, crust-like, very hard, and radially cracked. It is often at least partly covered with lichens, moss, or a combination of the two. It is sometimes greenish due to a covering of algae. Sometimes the fruiting body is shelf-like, with a flat or convex upper crust and a flat pore surface. Sometimes it grows on the underside at the base of dead branches with the pore surface exposed but the upper crust visible only on the curled margins (effused-reflexed).

The lower (pore) surface is dark brown or dark yellowish-, orangish-, or purplish-brown when fresh. It appears velvety and it bruises darker brown. Between the pores there are small flecks of whitish material that glitter when viewed from the side. Older inactive, weathered, or overwintered areas are gray or grayish-brown. The pores are up to (4 mm) deep and there are usually 3 to 5 pores per millimeter.

There is no stalk.

The flesh is reddish-brown to orangish-brown. When fresh it is soft and easily broken along the tubes. When cut in cross section it appears layered and there are white flecks (mycelial threads) running through it. When old it is hard and woody. It is inedible due to its woody texture.

The spore print is white.

 
     
 

Similar Species

 
     
     
 
Habitat and Hosts
 
 

Quaking aspen and bigtooth aspen

 
     
 
Ecology
 
 

Season

 
 

Year round

 
     
 
Distribution
 
 

Distribution Map

 

Sources

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

 
  4/5/2023      
         
 

Occurrence

 
 

Common

 
         
 
Taxonomy
 
  Kingdom Fungi (fungi)  
  Subkingdom Dikarya  
  Phylum Basidiomycota (club fungi)  
  Subphylum Agaricomycotina (jelly fungi, yeasts, and mushrooms)  
  Class Agaricomycetes (mushrooms, bracket fungi, puffballs, and allies)  
 

Order

Hymenochaetales  
 

Family

Hymenochaetaceae  
 

Genus

Phellinus  
       
 

This species was originally included as form of Fomes igniarius.

 
       
 

Synonyms

 
 

Fomes igniarius f. tremulae

Fomes tremulae

Ochroporus tremulae

 
       
 

Common Names

 
 

Aspen Bracket

Aspen Heart Rot

Aspen Trunk Rot

False Tinder Conk

 

 

 

 

 

 

 

Glossary

Conk

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

 

Lenticel

A corky, round or stripe-like, usually raised, pore-like opening in bark that allows for gas exchange.

 

 

 

 

 
 
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Luciearl

 
    Aspen Bracket   Aspen Bracket  
           
    Aspen Bracket   Aspen Bracket  
           
 
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  Luciearl
3/27/2023

Location: Lake Shore

Aspen Bracket  
           
 
MinnesotaSeasons.com Sightings
 
 

 

 

 

 

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Created: 4/5/2023

Last Updated:

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