Woolly chanterelle

Appearance

Adult fruit bodies are initially cylindrical, maturing to trumpet- or vase-shaped and reaching up to 30 cm high and up to 30 cm across. There is no clear demarcation between the cap and stipe. The stipe can be up to 15 cm tall and 6 cm wide, though it tapers to a narrower base. It is solid in younger specimens, though is often hollowed out by insect larvae in older. At higher elevations, two or three fruit bodies may arise from one stipe. Colored various shades of reddish- to yellowish-orange, the cap surface is broken into scales, with the spaces between more yellow and the scales themselves more orange. The most colorful specimens occur in warm humid weather. Older specimens are often paler.

The white flesh is fibrous and thick, though thins with age. Somewhat brittle, it can sometimes turn brown when cut or bruised. The smell has been reported as indistinct or "earthy and sweet", and the taste "sweet and sour". The spore-bearing undersurface is irregularly folded, forked or ridged rather than gilled and is pale buff or yellowish to whitish in color. These ridges are up to 4 mm high, and are decurrent—they extend below and run down the cap's attachment to the stipe, though irregularly so. The spore print is brownish, the spores ellipsoid with dimensions of 12.4–16.8 × 5.8–7.3 μm. The spore surface is roughened with ornamentations that can be made visible under the microscope by staining with methyl blue.

The fruit bodies can last for some considerable time, growing slowly over a month. Mushrooms in subalpine and alpine areas are typically heavy-set with a short stipe, their growth slower in the cold climate. This latter form is seen at lower altitudes in colder seasons. Smith gave this the name forma ''rainierensis''. Conversely, mushrooms at low altitudes, such as in the redwood forests, can grow and expand rapidly with large caps that have prominent scales. Smith described a paler form with a solid stipe from the Sierra Nevada as forma ''wilsonii''. American mycologist R. H. Petersen described an olive-capped form that is otherwise identical to the typical form. These forms are not recognised as distinct.

Naming

The related ''Turbinellus kauffmanii'', found in western North America, is similar-looking but has a pale brown cap. Younger specimens of the latter species also have a pungent smell. ''Turbinellus fujisanensis'', found in Japan, is another lookalike that has smaller spores than ''T. floccosus''.

Distribution

The fungus appears to form symbiotic relationships with various conifers including Douglas-fir , fir species such as momi fir , European silver fir and Khinghan fir , Pine species such as ''Pinus densiflora'' and western hemlock . In Mexico, the fungus associates with ''Abies religiosa''—the mycorrhizal association between these two species has been synthesized under controlled laboratory conditions. ''T. floccosus'' is more abundant in older stands of trees and places where there is more decomposed wood on the forest floor. The species occurs in coniferous forests in North America, particularly the western states in late summer and autumn. It is most abundant in rainy parts of the Pacific Northwest, northern California and the Sierra Nevada. It also occurs across Asia, having been recorded from Japan, North Korea, China, Tibet, India, Nepal and Pakistan. ''Turbinellus floccosus'' has been occasionally recorded from introduced conifer plantations in Australia.

Habitat

The fungus appears to form symbiotic relationships with various conifers including Douglas-fir , fir species such as momi fir , European silver fir and Khinghan fir , Pine species such as ''Pinus densiflora'' and western hemlock . In Mexico, the fungus associates with ''Abies religiosa''—the mycorrhizal association between these two species has been synthesized under controlled laboratory conditions. ''T. floccosus'' is more abundant in older stands of trees and places where there is more decomposed wood on the forest floor. The species occurs in coniferous forests in North America, particularly the western states in late summer and autumn. It is most abundant in rainy parts of the Pacific Northwest, northern California and the Sierra Nevada. It also occurs across Asia, having been recorded from Japan, North Korea, China, Tibet, India, Nepal and Pakistan. ''Turbinellus floccosus'' has been occasionally recorded from introduced conifer plantations in Australia.

Defense

''Turbinellus floccosus'' is poisonous to some people who eat it, but has been consumed without incident by others. Nausea, vomiting and diarrhea may occur, though are sometimes delayed by up to 8–14 hours. A tricarboxylic acid known as α-tetradecylcitric acid may be responsible for the extreme gastrointestinal symptoms. Laboratory experiments showed it increased tone of guinea pig smooth muscle of the small bowel , and that when given to rats, it led to mydriasis, skeletal muscle weakness, and central nervous system depression. ''Turbinellus floccosus'' contains more than double the amount of this acid than the related ''T. kauffmanii''.

Despite its toxicity, ''T. floccosus'' is one of the ten wild mushrooms most widely consumed by ethnic tribes in Meghalaya, northeast India, and is highly regarded by the Sherpa people in the vicinity of Sagarmatha National Park in Nepal. What is not known is whether the Indian populations of ''T. floccosus'' are nontoxic, or whether the local people have developed an immunity to it. It is also enjoyed in Mexico. American mycologist David Arora reported that some enjoyed it while he felt it had a strong sour taste.

The fruit body of ''T. floccosus'' produces oxylipin that have antifungal activity against the plant pathogens ''Colletotrichum fragariae'', ''C. gloeosporioides'', and ''C. acutatum''. Extracts of the fungus have shown in standard laboratory tests to have antimicrobial activity against several human pathogenic strains. ''T. floccosus'' also contains the spermidine derivative pistillarin, a bioactive compound that inhibits DNA damage by hydroxyl radicals generated by the Fenton reaction. Pistillarin is responsible for the green color obtained when iron salts are applied to the fruit body surface.