Polypores, also called bracket or shelf fungi, are a morphological group of

basidiomycete Basidiomycota () is one of two large divisions that, together with the Ascomycota, constitute the subkingdom Dikarya (often referred to as the "higher fungi") within the kingdom Fungi. Members are known as basidiomycetes. More specifically, Basid ...

-like

gilled mushrooms The Agaricales are an order of fungi in the division Basidiomycota. As originally conceived, the order contained all the agarics (gilled mushrooms), but subsequent research has shown that not all agarics are closely related and some belong in o ...

and

hydnoid fungi The hydnoid fungi are a group of fungi in the Basidiomycota with basidiocarps (fruit bodies) producing spores on pendant, tooth-like or spine-like projections. They are colloquially called tooth fungi. Originally such fungi were referred to the ge ...

that form large

fruiting bodies 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 ...

called conks, which are typically woody, circular, shelf- or bracket-shaped, with pores or tubes on the underside. Conks lie in a close planar grouping of separate or interconnected horizontal rows. Brackets can range from only a single row of a few caps, to dozens of rows of caps that can weigh several hundred pounds. They are mainly found on

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

s (living and dead) and

coarse woody debris Coarse woody debris (CWD) or coarse woody habitat (CWH) refers to fallen dead trees and the remains of large branches on the ground in forests and in rivers or wetlands.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). C ...

, and may resemble

mushroom A mushroom or toadstool is the fleshy, spore-bearing Sporocarp (fungi), fruiting body of a fungus, typically produced above ground on soil or another food source. ''Toadstool'' generally refers to a poisonous mushroom. The standard for the n ...

s. Some form annual fruiting bodies while others are perennial and grow larger year after year. Bracket fungi are typically tough and sturdy and produce their spores, called

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, within the pores that typically make up the undersurface. Most polypores inhabit tree trunks or branches consuming the wood, but some soil-inhabiting species form

mycorrhiza A mycorrhiza (; , mycorrhiza, or mycorrhizas) is a symbiotic association between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plant's rhizosphere, the plant root system and its surroundings. Mycorrhizae play ...

with trees. Polypores and the related

corticioid fungi The corticioid fungi are a group of fungi in the Basidiomycota typically having effused, smooth basidiocarps (fruit bodies) that are formed on the undersides of dead tree trunks or branches. They are sometimes colloquially called crust fungi or pa ...

are the most important agents of wood decay, playing a very significant role in

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 ...

and aiding carbon dioxide absorption by forest ecosystems. Several polypore species are serious pathogens of plantation trees and are major causes of timber spoilage. As polypores are much more diverse in old natural forests with abundant

dead wood Dead wood may refer to: *Dead tree (disambiguation) * Dead wood, the "straight man" in a double act *Dead Wood (novel), ''Dead Wood'' (novel), a 2009 novel by Chris Longmuir * Dead Wood (film), ''Dead Wood'' (film), a 2007 British film See also< ...

than in younger managed forests or plantations, a number of species have declined drastically and are under threat of extinction due to

logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucksdeforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...

. Polypores are used in traditional medicine, and they are actively studied for various industrial applications.

Taxonomy

Because bracket fungi are defined by their growth form rather than

phylogeny A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ...

, the group contains members of multiple

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

s. The beefsteak fungus, a well-known bracket fungus, is actually a member of the

agarics An agaric () is a type of fungal fruiting body characterized by the presence of a pileus (cap) that is clearly differentiated from the stipe (stalk), with lamellae (gills) on the underside of the pileus. It is a type of mushroom (or toadstool), ...

. Other examples of bracket fungi include chicken of the woods (or sulphur shelf),

birch bracket ''Fomitopsis betulina'' (previously ''Piptoporus betulinus''), commonly known as the birch polypore, birch bracket, or razor strop, is a common bracket fungus and, as the name suggests, grows almost exclusively on birch trees. The brackets bu ...

, dryad's saddle, artist's conk, and turkey tail. The name polypores is often used for a group that includes many of the hard or leathery fungi, which often lack a stipe, growing straight out of wood. "Polypore" is derived from the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

words ''poly'', meaning "much" or "many", and ''poros'', meaning "pore".

Classification

For most of 20th century polypores were treated as a family, the Polyporaceae. Reconstructions of family trees of fungi show that the

poroid {{Short pages monitor