Cookies on Plantwise Knowledge Bank

Like most websites we use cookies. This is to ensure that we give you the best experience possible.

Continuing to use www.plantwise.org/KnowledgeBank means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Plantwise Knowledge Bank
  • Knowledge Bank home
  • Change location
Plantwise Technical Factsheet

hoof fungus (Fomes fomentarius)

Host plants / species affected
Abies nordmanniana (Nordmann fir)
Abies sibirica (Siberian fir)
Acer (maples)
Aesculus indica (Indian horse-chestnut)
Alnus (alders)
Betula (birches)
Betula alleghaniensis (yellow birch)
Betula ermanii (Erman's birch)
Betula maximowicziana (monarch birch)
Betula platyphylla (Manchurian birch)
Betula pubescens (Downy birch)
Fagus (beeches)
Fagus crenata (Japanese beech)
Fagus sylvatica (common beech)
Fraxinus (ashes)
Juglans regia (walnut)
Picea abies (common spruce)
Platanus (planes)
Platanus acerifolia (London planetree)
Populus (poplars)
Populus nigra (black poplar)
Prunus (stone fruit)
Prunus serotina (black cherry)
Quercus (oaks)
Quercus petraea (durmast oak)
Quercus suber (cork oak)
Salix (willows)
Tilia (limes)
Tilia platyphyllos (large-leaved lime)
Tsuga canadensis (eastern hemlock)
Ulmus (elms)
List of symptoms/signs
Stems  -  discoloration
Stems  -  discoloration
Stems  -  internal discoloration
Stems  -  internal discoloration
Stems  -  lodging; broken stems
Stems  -  lodging; broken stems
Stems  -  mycelium present
Stems  -  mycelium present
Stems  -  rot
Stems  -  rot
Symptoms
F. fomentarius causes extensive white mottled rot in the wood of living and dead deciduous trees. The incipient stage of wood decay first appears as a light-brown discoloration, the wood remaining quite firm. With advanced decay the wood becomes yellowish-white, soft and spongy, and frequently contains brown to black zone lines (Boyce, 1938). Small radial cracks, filled with yellow mycelium, may develop giving the decay a mottled appearance. Infection of living trees occurs through branch stubs and wounds.
Prevention and control
There are no control measures currently recommended to prevent or reduce the decay of trees. Avoidance of mechanical stem injuries and proper pruning of branches may minimize damage, but these procedures are restricted to intensive, high-value stands or ornamental trees (Hiratsuka, 1987). Wound treatments, such as physically or chemically coating the stem wounds, may be effective in preventing invasion by the fungus. Some control may also be achieved by the removal of dead trees bearing sporophores (Allen et al., 1996). Early harvesting of stands before decay losses reach economically unacceptable levels can minimize damage. In aspen, there is significant clonal difference in the amount of decay (Wall, 1971), which could be an important factor for genetic improvement in the future.
Impact
Trees with advanced decay are unmerchantable as timber. Incipient decay or staining of the wood also makes it undesirable.
Related treatment support
 
External factsheets
University of Illinois Extension Factsheets, University of Illinois, 1999, English language
Zoomed image