Lactarius quietus
Encyclopedia
Lactarius quietus is a mushroom of the genus Lactarius
. It is easily identified by its oily scent and the concentric
bands on its cap. It is brown in colour, and is probably named after its matt, "quiet" surface and colouration. It is found exclusively under oak trees in Europe, where it grows solitarily or in scattered groups in autumn months. In North America, the variety L. quietus var. incanus is fairly common in the same habitat. The mushroom's edibility is disputed.
, who named it Agaricus quietus in the first volume of his Systema Mycologicum
, published in 1821. In his later Epicrisis Systematis Mycologici, published in 1838, Fries transferred the species to Lactarius. Subsequent attempts to reclassify the species were unsuccessful; in 1871, Paul Kummer
described the species as a member of Galorrheus, and in 1891 Otto Kuntze
classified it as Lactifluus, but today Fries's placement of the species in Lactarius is accepted. The specific epithet quietus means quiet or calm, and is possibly used to refer to the unintrusive colours of the cap.
The variety Lactarius quietus var. unicolor was described by Fries in the second volume of his Monographia Hymenomycetum Sueciae, published in 1863. The variety Lactarius quietus var. incanus was described by Lexemuel Ray Hesler
and Alexander H. Smith
in their 1979 North American species of Lactarius. The name incanus translates as hoary, referring to the white-coloured bloom which can sometimes be seen on the mushrooms.
Lactarius quietus is known by the common name
s Oak Milkcap, Oakbug Milkcap and the Southern Milkcap. Lactarius quietus var. incanus is commonly known as the Burnt Sugar Lactarius.
of 5 to 8 cm (2 to 3.1 in) across, which later flattens or develops a small depression in the center. In colour, the cap is a dull reddish-brown with a tint of cinnamon
, sometimes with darker concentric
bands or spots. This zoning is one of most distinctive features of the species. The cap is dry and matt, and not sticky when moist. It features a thick layer of firm, whitish-buff flesh. The stem
measures from 4 to 9 cm (1.6 to 3.5 in) in height, and is typically 10 to 15 mm (0.393700787401575 to 0.590551181102362 in) thick. It is cylindrical in shape, but is sometimes furrowed lengthways, and it lacks a ring
. It is concolourous with the cap, or a little darker, and is sometimes hollow. The brownish-white gills are slightly decurrent, and change colour with age to a pale reddish-brown with mauve hints. The milk
is white or cream in colour. The mushroom has a distinctive, strong oil
y smell, which has also been likened to bedbug
s and wet laundry. The spores are oval, with plentiful warts joined by numerous ridges, forming a well-developed network. The spores typically measure 7.5 to 9 by 6.5 to 7.5 microns
, and leave a cream print.
, and can be commonly found under oak trees. It can be confused with L. aquifluus and L. mutabilis, but both of these species are found in coniferous woodland.
trees, solitarily or in scattered groups, in soil. It can be found very commonly throughout autumn months. It is ectomycorrhizal, feeding symbiotically exclusively with oak, though studies have suggested it is also able to feed saprotrophically, growing from organic soil matter. L. quietus can be found only in Europe
; in the United Kingdom
, it is one of the one hundred most commonly encountered mushroom species. L. quietus var. incanus is found commonly in eastern North America.
Lactarius
Lactarius is a genus of mushroom-producing fungi. The genus, collectively known commonly as milk-caps, are characterized by the fact that they exude a milky fluid if cut or damaged...
. It is easily identified by its oily scent and the concentric
Concentric
Concentric objects share the same center, axis or origin with one inside the other. Circles, tubes, cylindrical shafts, disks, and spheres may be concentric to one another...
bands on its cap. It is brown in colour, and is probably named after its matt, "quiet" surface and colouration. It is found exclusively under oak trees in Europe, where it grows solitarily or in scattered groups in autumn months. In North America, the variety L. quietus var. incanus is fairly common in the same habitat. The mushroom's edibility is disputed.
Taxonomy and naming
L. quietus was first described and named by Swedish mycologist Elias Magnus FriesElias Magnus Fries
-External links:*, Authors of fungal names, Mushroom, the Journal of Wild Mushrooming.*...
, who named it Agaricus quietus in the first volume of his Systema Mycologicum
Systema Mycologicum
Systema Mycologicum is a systematic classification of fungi drawn up in 1821 by the Swedish mycologist and botanist Elias Fries. It took 11 years to complete....
, published in 1821. In his later Epicrisis Systematis Mycologici, published in 1838, Fries transferred the species to Lactarius. Subsequent attempts to reclassify the species were unsuccessful; in 1871, Paul Kummer
Paul Kummer
Paul Kummer was a priest, teacher, and scientist in Zerbst, Germany, known chiefly for his contribution to mycological nomenclature. Earlier classification of agarics by pioneering fungal taxonomist Elias Magnus Fries designated only a very small number of genera, with most species falling into...
described the species as a member of Galorrheus, and in 1891 Otto Kuntze
Otto Kuntze
Otto Carl Ernst Kuntze was a German botanist.-Biography:Otto Kuntze was born in Leipzig.An apothecary in his early career, he published an essay entitled Pocket Fauna of Leipzig. Between 1863 and...
classified it as Lactifluus, but today Fries's placement of the species in Lactarius is accepted. The specific epithet quietus means quiet or calm, and is possibly used to refer to the unintrusive colours of the cap.
The variety Lactarius quietus var. unicolor was described by Fries in the second volume of his Monographia Hymenomycetum Sueciae, published in 1863. The variety Lactarius quietus var. incanus was described by Lexemuel Ray Hesler
Lexemuel Ray Hesler
-External links:* Finding Aid for the Lexemuel Ray Hesler Collection, 1899-1982...
and Alexander H. Smith
Alexander H. Smith
Alexander Hanchett Smith was an American mycologist known for his extensive contributions to the taxonomy and phylogeny of the higher fungi, especially the agarics.-Early life:...
in their 1979 North American species of Lactarius. The name incanus translates as hoary, referring to the white-coloured bloom which can sometimes be seen on the mushrooms.
Lactarius quietus is known by the common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
s Oak Milkcap, Oakbug Milkcap and the Southern Milkcap. Lactarius quietus var. incanus is commonly known as the Burnt Sugar Lactarius.
Description
L. quietus typically has a convex capPileus (mycology)
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp that supports a spore-bearing surface, the hymenium. The hymenium may consist of lamellae, tubes, or teeth, on the underside of the pileus...
of 5 to 8 cm (2 to 3.1 in) across, which later flattens or develops a small depression in the center. In colour, the cap is a dull reddish-brown with a tint of cinnamon
Cinnamon
Cinnamon is a spice obtained from the inner bark of several trees from the genus Cinnamomum that is used in both sweet and savoury foods...
, sometimes with darker concentric
Concentric
Concentric objects share the same center, axis or origin with one inside the other. Circles, tubes, cylindrical shafts, disks, and spheres may be concentric to one another...
bands or spots. This zoning is one of most distinctive features of the species. The cap is dry and matt, and not sticky when moist. It features a thick layer of firm, whitish-buff flesh. The stem
Stipe (mycology)
thumb|150px|right|Diagram of a [[basidiomycete]] stipe with an [[annulus |annulus]] and [[volva |volva]]In mycology a stipe refers to the stem or stalk-like feature supporting the cap of a mushroom. Like all tissues of the mushroom other than the hymenium, the stipe is composed of sterile hyphal...
measures from 4 to 9 cm (1.6 to 3.5 in) in height, and is typically 10 to 15 mm (0.393700787401575 to 0.590551181102362 in) thick. It is cylindrical in shape, but is sometimes furrowed lengthways, and it lacks a ring
Volva (mycology)
The volva is a mycological term to describe a cup-like structure at the base of a mushroom that is a remnant of the universal veil. This macrofeature is important in wild mushroom identification due to it being an easily observed, taxonomically significant feature which frequently signifies a...
. It is concolourous with the cap, or a little darker, and is sometimes hollow. The brownish-white gills are slightly decurrent, and change colour with age to a pale reddish-brown with mauve hints. The milk
Latex
Latex is the stable dispersion of polymer microparticles in an aqueous medium. Latexes may be natural or synthetic.Latex as found in nature is a milky fluid found in 10% of all flowering plants . It is a complex emulsion consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins,...
is white or cream in colour. The mushroom has a distinctive, strong oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
y smell, which has also been likened to bedbug
Bedbug
Cimicidae are small parasitic insects. The most common type is Cimex lectularius. The term usually refers to species that prefer to feed on human blood...
s and wet laundry. The spores are oval, with plentiful warts joined by numerous ridges, forming a well-developed network. The spores typically measure 7.5 to 9 by 6.5 to 7.5 microns
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
, and leave a cream print.
var. incanus
L. quietus var. incanus is typically slightly larger than the nominate variety, and younger specimens feature a whitish bloom, after which the variant is named. It has a sweet smell reminiscent of maple syrupMaple syrup
Maple syrup is a syrup usually made from the xylem sap of sugar maple, red maple, or black maple trees, although it can also be made from other maple species such as the bigleaf maple. In cold climates, these trees store starch in their trunks and roots before the winter; the starch is then...
, and can be commonly found under oak trees. It can be confused with L. aquifluus and L. mutabilis, but both of these species are found in coniferous woodland.
Edibility
Lactarius quietus has been variously described as edible and inedible. The milk has a mild or slightly bitter taste. L. quietus var. incanus also has conflicting reports concerning its edibility, and so is not recommended.Habitat, ecology and distribution
L. quietus is found growing exclusively at the base of oakOak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
trees, solitarily or in scattered groups, in soil. It can be found very commonly throughout autumn months. It is ectomycorrhizal, feeding symbiotically exclusively with oak, though studies have suggested it is also able to feed saprotrophically, growing from organic soil matter. L. quietus can be found only in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
; in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
, it is one of the one hundred most commonly encountered mushroom species. L. quietus var. incanus is found commonly in eastern North America.