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Fomitopsis officinalis (Vill.) Bondartsev & Singer

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Scientific name
Fomitopsis officinalis
(Vill.) Bondartsev & Singer
Common names
práchnovček lekársky
pniarek (modrzewnik) lekarski
verpáník lékařský
Bitterer Lärchen-Baumschwamm, "Apothekerschwamm"
IUCN Specialist Group
Mushroom, Bracket and Puffball
Assessment status
Assessment date
IUCN Red List Category
IUCN Red List Criteria
Kałucka, I.L. & Svetasheva, T.
Mueller, G.M.

Assessment Notes

The content on this page is fetched from The IUCN Red List of Threatened Species: https://www.iucnredlist.org/species/75104087/75104095


Fomitopsis officinalis is a wood-inhabiting parasitic fungus forming distinctive conks that can be more than 50 cm long, hoof-shaped or columnar. It is widely distributed in the the northern Hemisphere, mostly in subalpine, montane hypoarctic and boreal old-growth forests on large and old coniferous trees (e.g., Larix). It is commonly known as Agarikon and has since ancient times been collected for medical purposes. It is globally reported as rare or extremely rare and has declined significantly during the last centuries.

The species is assessed as EN under criterion A2ad because of a 70-75% population reduction in the past caused by habitat degradation and loss and collection of basidiocarps for medical purposes.  It is assumed that decline will continue, but at a lower rate.

Geographic range

It is a Holarctic species with predominantly montane hypoarctic and boreal distribution. It is known from North America (mainly Pacific Northwest Coast), Europe (especially mountain areas), Ural, Asia (Siberia, Far East, China, Mongolia, Japan, Korea, India), and Africa (Morocco Atlas Mts). The species' distribution approximately coincides with Larix spp in Eurasia and Larix, Pseudotsuga and some species of Picea in North America.

Population and Trends

Fomitopsis officinalis has declined significantly during the last centuries. There are many records from different countries and continents about continuing reduction of population and decrease of habitats compared with the first half of the 20th century. Examples include: “There are 109 records of F. officinalis in British Columbia since 1940 (when data collection first began), but only 19 of those records were added in the past 20 years. It remains to be determined if the reduced sightings and collections are a result of habitat loss (reduction of old growth sites)” (Callan 2000); “Neuman (1914) reported that ‘‘various collectors’’ had noted Fomitopsis officinalis occurring on larch in northern Wisconsin. Although a few reports of this fungus have been confirmed from the Great Lakes region (Gilbertson and Ryvarden 1986), F. officinalis no longer is considered to occur in the Midwest” (Lindner et al. 2006); Up to the 18th century the species was quite frequent in Poland, and in some places very common; in the 20th century it was almost completely eradicated and at present, only six localities are known (Łuszczyńska and Łuszczyński 2009). “Everywhere in the Asian part of Russia it is now a rare species. During 26 years of investigation it was found only 46 times in 26 localities. Today the species is rare in regions where it earlier was common. In Altai, Murashkinsky (1939) mentioned, that in the beginning of 20th century 10% of the larches were infected by L. officinalis. In 2001 we found it there only once” (Mukhin et al. 2005). The species was quite common in the Irkutsk region and Buryatia Republik, but it has been heavily harvested (in tons) for medicinal purposes. 

The present number of known localities in Europe approaches 100 of which 80% are in the French and Swiss Alps. In Lithuania and Spain there are no records after 1968. In France, Poland, Slovakia and Slovenia a decrease has been noticed for the last 50 to 100 years. A slight increase in the number of sites was reported in Switzerland, probably connected with the cessation of collecting and more sustainable forest management. In Russia, about 50 sites are registered in scientific sources, but it may occur in about 1000 sites or even more. It is widespread but rare in western North America. It is rare in Japan, and only seen in mature Larix or Picea forests; reported from several places including Hokkaido Pref., Shizuoka Pref. and Tochigi Pref.

The species is on the national Red Lists of several European countries, e.g., Austria, France, Germany, Lithuania, Poland, Russia (regional Red Data Books), Slovakia, Switzerland (Fraiture and Otto 2015). It is protected by law in Germany, Lithuania, Poland and Slovenia. It has been listed as threatened in Europe by Dahlberg and Croneborg (2003). 

Fomitopsis officinalis has long lived mycelia growing in wood and a long generation length, perhaps over 50 years. It is assessed to have declined due to past and ongoing habitat loss and continuous harvesting, with the decline exceeding 50% over the past three generations (cf Mukhin et al. 2005) and even steeper in Europe and North America. Thus, F. officinalis is assessed as Endangered on a global scale.

Population Trend: decreasing

Habitat and Ecology

Fomitopsis officinalis is a tree parasite that continues to live as a saprotroph after the death of the host tree. Most frequently it occurs on different species of Larix, less frequently on Pseudotsuga, Abies, Pinus, Picea, Tsuga and Cedrus. With the exception of Spain, where it was found on Pinus nigra subsp. salzmannii, it occurs in Europe exclusively on larch trees: Larix decidua, L. decidua var. polonica, L. sibirica. In Asia, it grows also on L. gmelinii and L. cajanderii, and rarely on Pinus sibirica and P. sylvestris. In North America, it was found also on Pseudotsuga menziesii, Picea sitchensis, Pinus ponderosa, and Larix occidentalis. It obviously prefers old and thick trees and hence old-growth forests predominantly in mountain areas. It causes brown rot of wood.  Perennial basidiocarps have a long life up to 60-70 years (Bondartsev 1953). They grow up to 40x65 cm (Mukhin et al. 2005) and can reach weight up to 10 kg (Piętka and Szczepkowski 2004). They appear on the host tree trunk from the base up to over 20 m above, rarely on thick branches, usually in the place of infection after a few decades of its development (Konev 1972). The fungus can occur both on living trees and on their trunks and stumps after death. 

In Europe, the species is associated mainly with virgin/old growth subalpine larch forests in the Alps, larch forests in the Świętokrzyskie Mountains and lowland larch forests of Eastern Europe. It occurs almost exclusively in natural forests (very rarely in plantations or in parks) (Fraiture and Otto 2015). It is found most frequently on the trees suffering from environmental stress (suboptimal habitat, weakening caused by abiotic reasons or damage, the presence of some other fungal parasites) (Piętka and Szczepkowski 2004).


Threats to this species include logging of subalpine / montane, boreal and subarctic forests, cutting of larch forests and single old veteran trees of Larix spp. and other conifer hosts (also as part of regular management and removing infested/injured/ill-shaped trees); changes in the age and tree species structure of forests; degradation and loss of habitats due to different economic purposes (logging, building of tourists and sports constructions); and collection of basidiomata for medicinal purposes.

Conservation Actions

Actions required for the conservation of Fomitopsis officinalis are the establishment and appropriate management of areas protected by law (national parks, nature reserves, etc.) covering the places of its occurrence, active protection promoting the presence of larch and its regeneration, the prohibition of logging and removing of single old larch trees (and other hosts), the prohibition of unrestricted collection of basidiomata (especially for trade), and strict control of the fungus trade.

The species is protected by law in Germany, Lithuania, Poland and Slovenia.

Use and Trade

The basidiomata have been widely used since ancient times for medical purposes. It  has been reported to possess antiviral and actibacterial properties, and to be a panaceum for all ailments (see Piętka and Szczepkowski 2004 for detailed review).

Source and Citation

Kałucka, I.L. & Svetasheva, T. 2019. Fomitopsis officinalis. The IUCN Red List of Threatened Species 2019: e.T75104087A75104095. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T75104087A75104095.en .Accessed on 1 February 2024

Country occurrence