''Phaeolus schweinitzii'', commonly known as velvet-top fungus, dyer's polypore, dyer's mazegill, or pine dye polypore, is a

fungal A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

plant pathogen Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomyc ...

that causes

butt rot Butt rot is a disease of plants, mostly trees, caused by fungi. The fungus attacks the moist, poorly protected undersurface of tree trunk's thickest part (the "butt" above the root, as opposed to "top"), where the end of the stem makes contact wi ...

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 single ...

s such as Douglas-fir,

spruce A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal (taiga) regions of the Earth. ''Picea'' is the sole genus in the subfami ...

fir Firs (''Abies'') are a genus of 48–56 species of evergreen coniferous trees in the family (biology), family Pinaceae. They are found on mountains throughout much of North America, North and Central America, Europe, Asia, and North Africa. The ...

, hemlock,

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. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...

, and larch. ''P. schweinitzii'' is a

polypore Polypores are a group of fungi that form large fruiting bodies with pores or tubes on the underside (see Delimitation for exceptions). They are a morphological group of basidiomycetes-like gilled mushrooms and hydnoid fungi, and not all polypor ...

, although unlike

bracket fungi Polypores are a group of fungi that form large fruiting bodies with pores or tubes on the underside (see Delimitation for exceptions). They are a morphological group of basidiomycetes-like gilled mushrooms and hydnoid fungi, and not all polypor ...

the fruiting body may appear terrestrial when growing from the roots or base of the host tree. The fruiting bodies, appearing in late summer or fall, commonly incorporate blades of grass, twigs, or fallen pine needles as they grow. They are tannish with darker brown centres, with orange to pale margins on young specimens. They may grow beyond 25 cm in diameter. As the fruiting bodies age, the pore surface turns from yellow to greenish yellow, the top becomes darker, and the yellow-brown flesh becomes harder and more wood-like. The pores bruise brown. The spores are white, elliptical, smooth, and inamyloid. The effect, impact and significance of infection by this fungus is rooted in the fact that it causes brown rot, which degrades the cellulose. Thus there is a loss of tensile strength which often leads to brittle fracture near the stem base, even at a fairly early stage of decay. Decay initiated above ground can lead to branch snap or breakout. ''P. schweinitzii'' is native to

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

and

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...

, and has been identified as an exotic species in

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, and

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

. It is not edible. As its common name suggests, the dyer's polypore is an excellent natural source of green, yellow, gold, or brown

dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution an ...

, depending on the material dyed and the

mordant A mordant or dye fixative is a substance used to set (i.e. bind) dyes on fabrics by forming a coordination complex with the dye, which then attaches to the fabric (or tissue). It may be used for dyeing fabrics or for intensifying stains in ...

used. ''P. schweinitzii'' is named after Lewis David de Schweinitz, a

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

-born Moravian minister and important early

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

mycologist Mycology is the branch of biology concerned with the study of fungus, fungi, including their genetics, genetic and biochemistry, biochemical properties, their Taxonomy (biology), taxonomy and ethnomycology, their use to humans, including as a so ...

. Similar species include '' Heterobasidion irregulare'', '' H. occidentale'', ''

Inonotus dryophilus ''Inonotus dryophilus'' is a plant pathogen. References External links Index FungorumUSDA ARS Fungal Database Fungal plant pathogens and diseases dryophilus ''Dryophilus'' is a genus of beetles in the family Ptinidae. There are about ...

'', and ''

Onnia tomentosa ''Onnia tomentosa'' is a species of fungus in the family (biology), family Hymenochaetaceae commonly known as the woolly velvet polypore. It is frequently found in coniferous forests at higher altitudes, often growing in large groups, rather rare ...

''.

References

{{Taxonbar, from=Q1314913 Wood-decay fungi Fomitopsidaceae Fungal tree pathogens and diseases Fungi described in 1821 Fungi of Europe Fungi of North America Inedible fungi Natural dyes Taxa named by Elias Magnus Fries