''Fomitopsis pinicola'', is a stem decay

fungus A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

common on softwood and hardwood trees. Its conk (fruit body) is known as the red-belted conk or red-belted bracket. The

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

is common throughout

temperate In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

. It is a decay fungus that serves as a small-scale disturbance agent in coastal rainforest ecosystems. It influences stand structure and succession in temperate rainforests. It performs essential

nutrient cycling A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyc ...

functions in forests.FS-R10-FHP. 2014. Forest Health Conditions in Alaska 2013. Anchorage, Alaska. USDA Forest Service, Alaska Region. Publication R10-PR-035.81 PAGES 40-42. As well as a key producer of brown rot residues that are stable soil components in

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

ous forest ecosystems. It has been reported that mushrooms have significant antioxidant activity.

Description

The cap is hoof-shaped or triangular, and sometimes shelflike. It is hard and tough, and up to 30 cm or more across and 15 cm thick. Its surface is more or less smooth, at first orange-yellow with a white margin, later dark reddish to brown and then frequently with an orange margin. The pore surface is pale yellow to leather-brown, 3–4 pores per mm. It grows as thick shelves on live and dead coniferous or (less commonly) deciduous trees.FS-R10-FHP. 2014. Mushrooms of the National Forests in Alaska. Anchorage, Alaska. USDA Forest Service, Alaska Region. Publication R10-RG-209. PAGES 30 & 31. The

spores In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plant ...

are pale yellow and smooth. The species also grows as a layer of tubes on the bottom of fallen wood. The

fruiting body The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

of ''Fomitopsis pinicola'' is called the ''conk''. It is a woody, pileate fruiting body with pores lined with

basidia A basidium (: basidia) is a microscopic spore-producing structure found on the hymenophore of reproductive bodies of basidiomycete fungi. The presence of basidia is one of the main characteristic features of the group. These bodies are also ...

on its underside. As in other polypores, the fruiting body is perennial with a new layer of pores produced each year on the bottom of the old pores. The pores are whitish when young and become somewhat brownish in age. This mushroom is inedible due to its woody texture, but it is useful as tinder. The basidiocarps of the fungus have been reported to have medicinal usages in Asia. There is currently a splitting of ''F. pinicola'' occurring to isolate distinct species that have all previously been classified as ''F. pinicola.'' DNA analysis supports splitting ''F. pinicola'' into three groups- ''F. pinicola, F. mounceae, and F. schrenkii''. ''Fomitopsis pinicola'' is found in

and

, ''Fomitopsis mounceae'' is on the east coast of the US, west coast of the US and midwestern US, and ''F. schrenkii'' is found at higher elevations in the latitude of the Rocky Mountains, from

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

to central

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

Similar species

Similar species include ''

Ganoderma lucidum ''Ganoderma lucidum'', commonly known as the reishi, varnished conk, lacquered bracket, or ling chih, is a red-colored species of '' Ganoderma'' with a limited distribution in Europe and parts of China, where it grows on decaying hardwood trees. ...

'', '' Laricifomes officinalis'', and '' Heterobasidion annosum''.

Stem decay characteristics

Most of the stem decay (heart rot) in mature forests that results from this fungus does not interfere with the normal growth and physiological processes of live trees since the

vascular system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart a ...

is not affected. It is classified as a brown rot, which primarily degrades

cellulose Cellulose is an organic compound with the chemical formula, formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of glycosidic bond, β(1→4) linked glucose, D-glucose units. Cellulose is an important s ...

in tree stands. The early stage of wood decay appears as yellowish to brownish discoloration with the advanced stage appearing as a brown and crumbly breaking into cubical pieces. Wood impacted by this fungus may become more brittle and prone to breakage in high winds, and cannot be used for pulp production. This species requires exposed wood of wounds for entry, continuing their decay after the tree dies. On dead trees, the fungus general affects the sapwood and then progresses into

heartwood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

. The fruiting bodies of the fungus produce abundant basidocarps and

basidiospore A basidiospore is a reproductive spore produced by basidiomycete fungi, a grouping that includes mushrooms, shelf fungi, rusts, and smuts. Basidiospores typically each contain one haploid Ploidy () is the number of complete sets of chromos ...

s which are generally dispersed in air currents and germinate upon contact with wood or other substrates, but the actual degradation of the wood is by the thread-like vegetative part of the fungus inside the trees. The fungus can occur anywhere on roots or the stem, but is most common low on the bole, where frequent wounds promote infection.FS-R10-FHp. 2014. Managing Heart Rot in Live Trees for Wildlife Habitat in Young-Growth Forests of Coastal Alaska. Anchorage, Alaska. USDA Forest Service, Alaska Region. Publication PNW-GTR-890. PAGES 4 – 9.

Ecology

This stem decay fungus is found on live conifer trees in

southeast Alaska Southeast Alaska, often abbreviated to southeast or southeastern, and sometimes called the Alaska(n) panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian provi ...

such as

Western hemlock ''Tsuga heterophylla'', the western hemlock or western hemlock-spruce, is a species of hemlock native to the northwest coast of North America, with its northwestern limit on the Kenai Peninsula, Alaska, and its southeastern limit in northern ...

Mountain hemlock ''Tsuga mertensiana'', known as mountain hemlock, is a species of hemlock native to the west coast of North America, found between Southcentral Alaska and south-central California. Description ''Tsuga mertensiana'' is a large evergreen conifer ...

White spruce White spruce is a common name for several species of spruce (''Picea'') and may refer to: * '' Picea engelmannii'', native to the Rocky Mountains and Cascade Mountains of the United States and Canada * ''Picea glauca ''Picea glauca'', the whi ...

, Lutz spruce and

Sitka spruce ''Picea sitchensis'', the Sitka spruce, is a large, coniferous, evergreen tree growing to just over tall, with a trunk diameter at breast height that can exceed 5 m (16 ft). It is by far the largest species of spruce and the fifth- ...

. The tree stem decay is caused by the fungus when it invades and colonizes the wood of living trees and decomposes the wood before the tree is dead. This brown rot fungus degrades only cellulose, leaving the other primary constituents of wood,

lignin Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidit ...

, as a considerably less dense but fairly stable residual structure that is suitable for excavation by

woodpeckers Woodpeckers are part of the bird family Picidae, which also includes the piculets, wrynecks and sapsuckers. Members of this family are found worldwide, except for Australia, New Guinea, New Zealand, Madagascar and the extreme polar regions. ...

. This fungus is normally found on dead

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as cu ...

s, but can be found on all conifers. It can also be observed growing on large stem wounds, broken tops, and dead tissue of live trees. In mature forests, these stem decay fungi cause enormous annual wood volume loss of Alaska's major tree species. Approximately one-third of the old-growth timber board-foot volume in Southeast Alaska is defective, largely due to decay from this type of fungus. Conversely, there is very little decay in young-growth stands without prevalent wounding from commercial

thinning In agricultural sciences, thinning is the removal of some plants, or parts of plants, to make room for the growth of others. Selective removal of parts of a plant such as branches, buds, or roots is typically known as '' pruning''. In forestry ...

activities, wind damage, or animal feeding. By predisposing large old trees to bole breakage and windthrow, stem decays serve as important small-scale disturbance regimes in these temperate rainforest ecosystems where fire and other large-scale disturbances are uncommon. This stem decay creates canopy gaps, influences stand structure and succession, increases

biodiversity Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...

, and enhances wildlife habitat. The fungus also performs essential nutrient cycling functions in these forests by decomposing stems, branches, roots, and boles of dead trees. Cavities created by the fungus in standing trees provide crucial habitat for many wildlife species including

bears Bears are carnivoran mammals of the family Ursidae (). They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout most o ...

voles Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molar (tooth), molars (high-crowned with angular cusps i ...

squirrels Squirrels are members of the family (biology), family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and ...

, and a number of

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

species. The lack of disturbance in these areas and longevity of individual trees allows ample time for this slow-growing decay fungus to cause significant decay. There is a growing interest in acquiring methods to promote earlier development of stem decays in second-growth stands to achieve wildlife and other non-timber objectives. Image:Fomitopsis_pinicola_2.JPG, Underside of conk showing the typical round pores. Image:Fomitopsis_pinicola_3.JPG, Younger specimens like these often show more orange colours. File:Fomitopsis pinicola 2023 G1.jpg, Fomitopsis pinicola on a dead tree in Ukraine.

References

* "Danske storsvampe. Basidiesvampe" key to Danish basidiomycetesJ.H. Petersen and J. Vesterholt eds. Gyldendal. Viborg, Denmark, 1990.
Entry of ''Fomitopsis pinicola''
at Fungal Databases, Systematic Botany and Mycology Laboratory Nomenclature Database, U.S. Department of Agriculture, Agricultural Research Service.

External links

{{Taxonbar, from=Q1928270 pinicola Fungi described in 1810 Inedible fungi Fungus species