Suillus brevipes
Encyclopedia
Suillus brevipes is a species of fungus
in the Boletaceae
family. First described by American mycologists in the late 19th century, it is commonly
known as the stubby-stalk or the short-stemmed slippery Jack. The fruit bodies
(mushroom
s) produced by the fungus are characterized by a chocolate to reddish-brown cap
covered with a sticky layer of slime, and a short whitish stem
that does not have a partial veil
. The cap can reach a diameter of about 10 cm (3.9 in), while the stem is up to 6 cm (2.4 in) long and 2 cm (0.78740157480315 in) thick. Like other bolete
mushrooms, S. brevipes produces spores
in a vertically arranged layer of spongy tubes with openings that form a layer of small yellowish pores on the underside of the cap.
Suillus brevipes grows in a mycorrhizal association with various species of coniferous trees, especially lodgepole
and ponderosa pine
. The fungus is found throughout North America, and has been introduced
to several other countries via transplanted pines. In the succession
of mycorrhizal fungi associated with the regrowth of jack pine
after clearcutting
or wildfire
s, S. brevipes is a multi-stage fungus, found during all stages of tree development. The mushrooms are edible
, and are high in the essential
fatty acid linoleic acid
.
in 1874. In 1885, Charles Horton Peck
, who had found specimens in pine woods of Albany County, New York
, explained that the species name was a taxonomic homonym (Boletus viscosus was already in use for another species named by Ventenat
in 1863), and so renamed it to Boletus brevipes. Its current name was assigned by German Otto Kuntze
in 1898. William Alphonso Murrill renamed it as Rostkovites brevipes in 1948; the genus Rostkovites is now considered to be synonymous
with Suillus
.
Agaricales
specialist Rolf Singer
included Suillus brevipes in the subsection Suillus of genus Suillus
, an infrageneric (a taxonomic
level below genus) grouping of species characterized by a cinnamon-brown spore print
, and pores less than 1 mm wide. Molecular phylogenetic analyses of ribosomal DNA
sequences shows that the most closely related species to Suillus brevipes include S. luteus
, S. pseudobrevipes
, and S. weaverae (formerly Fuscoboletinus weaverae).
The specific epithet is derived from the Latin
brevipes, meaning "short-footed". The mushroom is commonly known
as the "stubby-stalk" or the "short-stemmed slippery Jack".
is deep brown to reddish-brown, later fading to tan
with age, and it does not bruise with handling. The cap surface is smooth, and, depending on the moisture in the environment, may range from sticky to the touch to slimy. Depending on its maturity, the cap shape may range from spherical to broadly convex. The cap is medium sized, 5 – wide, and the cap cuticle
can be peeled from the surface. The tubes are yellow, becoming olive-green with age, and they have an attachment to the stem that ranges from adnate (with most of the tube fused to the stem) to decurrent
(with the tubes broadly attached, but running somewhat down the length of the stem). They are typically up to 1 cm (0.393700787401575 in) deep, and there are about 1–2 tube mouths (pores) per millimeter. The pores are pale yellow, round, 1–2 mm wide, and do not change color when bruised.
The stem
is white to pale yellow, dry, solid, not bruising, and pruinose (having a very fine whitish powder on the surface). A characteristic feature of many Suillus species are the glandular dots found on the stem—clumps of hypha
l cell ends through which the fungus secretes various metabolic wastes, leaving a sticky or resinous "dot". In S. brevipes, the form of the glandular dots is variable: they may be absent, slightly underdeveloped or obscurely formed with age. The stem is usually short in comparison to the diameter of the cap, typically 2 – long and 1 – thick. It is either of equal width throughout, or may taper downwards; its surface bears minute puncture holes at maturity, and is it slightly fibrous at the base. The flesh
of the mushroom is initially white, but turns pale yellow in age. The odor and taste are mild. The spore print
is cinnamon-brown.
are elliptical to oblong, smooth, and have dimensions of 7–10 by 3–4 µm
. The spore-bearing cells, the basidia, are thin-walled, club-shaped to roughly cylindrical, and measure 2–25 by 5–7 µm. They bear either two or four spores. The pleurocystidia (cystidia that are found on the face of a gill) are roughly cylindrical with rounded ends, thin-walled, and 40–55 by 5–8 µm. The cells often have brown contents, and in the presence of 2% potassium hydroxide
(KOH) will appear hyaline
(translucent) or vinaceous (red wine-colored); in Melzer's reagent
they become pale yellow or brown. The cheilocystidia (cystidia found on the edge of a gill) are 30–60 by 7–10 µm, club-shaped to almost cylindrical, thin-walled, with brown incrusting material at the base, and arranged like a bundle of fibers. In KOH they appear hyaline, and are pale yellow in Melzer's reagent. Caulocystidia (found on the stem) are 60–90 by 7–9 µm, mostly cylindrical with rounded ends, and arranged in bundles with brown pigment
particles at the base. The caulocystidia stain vinaceous in KOH. The cuticle
of the cap is made of a layer of interwoven gelatinous hyphae that are individually 2–5 µm thick; the gelatinous hyphae are responsible for the sliminess of the cuticle. There are no clamp connection
s in the hypha
e.
, S. brevipes is edible
, and the mushroom is considered choice by some. The odor is mild, and the taste mild or slightly acidic. Field guide
s typically recommended to remove the slimy cap cuticle, and, in older specimens, the tube layer before consumption. The mushrooms are common in the diet of grizzly bear
s in Yellowstone National Park
.
The fatty acid
composition of S. brevipes fruit bodies has been analyzed. The cap contained a higher lipid
content than the stem—18.4% of the dry weight
, compared to 12.4%. In the cap, linoleic acid
made up 50.7% of the total lipids (65.7% in the stem), oleic acid
was 29.9% (12.4% in the stem), followed by palmitic acid
at 10.5% (12.6% in the stem). Linoleic acid—a member of the group of essential fatty acid
s called omega-6 fatty acid
s—is an essential dietary requirement for humans.
has a shorter stem, and distinct raised granules on the stem. S. brevipes is differentiated from S. albidipes by not having a cottony roll of velar tissue (derived from a partial veil
) at the margin when young. S. pallidiceps is by distinguished its pale yellow cap color; and S. albivelatus has a veil. S. pungens
has a characteristic pungent odor, compared to the mild smell of S. brevipes, and like S. granulatus, has glandular dots on the stem.
l fungus, and it develops a close symbiotic
association with the roots of various tree species, especially pine
. The underground mycelia form a sheath around the tree rootlets, and the fungal hyphae penetrate between the cortical
cells of the root, forming ectomycorrhizae. In this way, the fungus can supply the tree with minerals, while the tree reciprocates by supplying carbohydrate
s created by photosynthesis
. In nature, it associates with two- and three-needle pines, especially lodgepole
and ponderosa pine
. Under controlled laboratory conditions, the fungus has been shown to form ectomycorrhizae with ponderosa, lodgepole, loblolly
, eastern white
, patula, pond
, radiata, and red pine
s. In vitro
mycorrhizal associations formed with non-pine species include Pacific madrone
, bearberry
, western larch
, Sitka spruce
, and coast Douglas-fir
. Fungal growth is inhibited by the presence of high levels of the heavy metals cadmium
(350 ppm), lead
(200 ppm), and nickel
(20 ppm).
During the regrowth of pine trees after disturbance like clearcutting
or wildfire
, there appears an orderly sequence of mycorrhizal fungi as one species is replaced by another. A study on the ecological succession
of ectomycorrhizal fungi in Canadian jack pine
forests following wildfire concluded that S. brevipes is a multi-stage fungus. It appears relatively early during tree development; fruit bodies were common in 6-year old tree stands, and the fungus colonized the highest proportion of root tips. The fungus persists throughout the life of the tree, having been found in tree stands that were 41, 65, and 122 years old. There is, however, a relative reduction in the prevalence of the fungus with increasing stand age, which may be attributed to increased competition from other fungi, and a change in habitat brought about by closure of the forest canopy. Generally, S. brevipes responds favorably to silvicultural
practices such as thinning and clearcutting. A 1996 study demonstrated that fruit bodies increased in abundance as the severity of disturbance increased. It has been suggested that the thick-walled, wiry rhizomorphs produced by the fungus may serve as an adaptation that helps it to survive and remain viable for a period of time following disturbance.
growing under planted Pinus caribaea, where it is thought to have been introduced
inadvertently from North Carolina
by the USDA Forest Service in 1955. Other introductions have also occurred in exotic pine plantations in Argentina, India, New Zealand, Japan, and Taiwan.
Fungus
A fungus is a member of a large 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, Fungi, which is separate from plants, animals, and bacteria...
in the Boletaceae
Boletaceae
Boletaceae are a family of mushrooms, primarily characterized by developing their spores in small pores on the underside of the mushroom, instead of gills, as are found in agarics. Nearly as widely distributed as agarics, they include the Cep or King Bolete , much sought after by mushroom hunters...
family. First described by American mycologists in the late 19th century, it is commonly
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...
known as the stubby-stalk or the short-stemmed slippery Jack. The fruit bodies
Basidiocarp
In fungi, a basidiocarp, basidiome or basidioma , is the sporocarp of a basidiomycete, the multicellular structure on which the spore-producing hymenium is borne. Basidiocarps are characteristic of the hymenomycetes; rusts and smuts do not produce such structures...
(mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s) produced by the fungus are characterized by a chocolate to reddish-brown cap
Pileus (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...
covered with a sticky layer of slime, and a short whitish 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...
that does not have a partial veil
Partial veil
thumb|150px|right|Developmental stages of [[Agaricus campestris]] showing the role and evolution of a partial veilPartial veil is a mycological term used to describe a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics...
. The cap can reach a diameter of about 10 cm (3.9 in), while the stem is up to 6 cm (2.4 in) long and 2 cm (0.78740157480315 in) thick. Like other bolete
Bolete
A bolete is a type of fungal fruiting body characterized by the presence of a pileus that is clearly differentiated from the stipe, with a spongy surface of pores on the underside of the pileus...
mushrooms, S. brevipes produces spores
Basidiospore
A basidiospore is a reproductive spore produced by Basidiomycete fungi. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. In grills under a cap of one common species in the phylum of...
in a vertically arranged layer of spongy tubes with openings that form a layer of small yellowish pores on the underside of the cap.
Suillus brevipes grows in a mycorrhizal association with various species of coniferous trees, especially lodgepole
Lodgepole Pine
Lodgepole Pine, Pinus contorta, also known as Shore Pine, is a common tree in western North America. Like all pines, it is evergreen.-Subspecies:...
and ponderosa pine
Ponderosa Pine
Pinus ponderosa, commonly known as the Ponderosa Pine, Bull Pine, Blackjack Pine, or Western Yellow Pine, is a widespread and variable pine native to western North America. It was first described by David Douglas in 1826, from eastern Washington near present-day Spokane...
. The fungus is found throughout North America, and has been introduced
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
to several other countries via transplanted pines. In the succession
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
of mycorrhizal fungi associated with the regrowth of jack pine
Jack Pine
Jack pine is a North American pine with its native range in Canada east of the Rocky Mountains from Northwest Territories to Nova Scotia, and the northeast of the United States from Minnesota to Maine, with the southernmost part of the range just into northwest Indiana...
after clearcutting
Clearcutting
Clearcutting, or clearfelling, is a controversial forestry/logging practice in which most or all trees in an area are uniformly cut down. Clearcutting, along with shelterwood and seed tree harvests, is used by foresters to create certain types of forest ecosystems and to promote select species that...
or wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
s, S. brevipes is a multi-stage fungus, found during all stages of tree development. The mushrooms are edible
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, and are high in the essential
Essential fatty acid
Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest because the body requires them for good health but cannot synthesize them...
fatty acid linoleic acid
Linoleic acid
Linoleic acid is an unsaturated n-6 fatty acid. It is a colorless liquid at room temperature. In physiological literature, it has a lipid number of 18:2...
.
Taxonomy
The species was first described scientifically as Boletus viscosus by American mycologist Charles FrostCharles Christopher Frost
Charles Christopher Frost was an American botanist. He described several species of fungi from the New England area of the United States. In one paper, Frost described 22 new species of boletes, and he was later credited with the discovery of three additional species. His personal herbarium of...
in 1874. In 1885, Charles Horton Peck
Charles Horton Peck
Charles Horton Peck, born March 30, 1833 in Sand Lake, New York, died 1917 in Albany, New York, was an American mycologist of the 19th and early 20th centuries...
, who had found specimens in pine woods of Albany County, New York
Albany County, New York
Albany County is a county located in the U.S. state of New York, and is part of the Albany-Schenectady-Troy Metropolitan Statistical Area. The name is from the title of the Duke of York and Albany, who became James II of England . As of the 2010 census, the population was 304,204...
, explained that the species name was a taxonomic homonym (Boletus viscosus was already in use for another species named by Ventenat
Étienne Pierre Ventenat
Étienne Pierre Ventenat was a French botanist born in Limoges. He was the brother of naturalist Louis Ventenat ....
in 1863), and so renamed it to Boletus brevipes. Its current name was assigned by German 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...
in 1898. William Alphonso Murrill renamed it as Rostkovites brevipes in 1948; the genus Rostkovites is now considered to be synonymous
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
with Suillus
Suillus
Suillus is a genus of basidiomycete fungi in the family Suillaceae and order Boletales. Species in the genus are associated with coniferous trees, and are mostly distributed in northern temperate locations, although some species have been introduced to the Southern Hemisphere.-Taxonomy:The genus...
.
Agaricales
Agaricales
The fungal order Agaricales, also known as gilled mushrooms , or euagarics, contains some of the most familiar types of mushrooms. The order has 33 extant families, 413 genera, and over 13000 described species, along with five extinct genera known only from the fossil record...
specialist Rolf Singer
Rolf Singer
Rolf Singer was a German-born mycologist and one of the most important taxonomists of gilled mushrooms in the 20th century....
included Suillus brevipes in the subsection Suillus of genus Suillus
Suillus
Suillus is a genus of basidiomycete fungi in the family Suillaceae and order Boletales. Species in the genus are associated with coniferous trees, and are mostly distributed in northern temperate locations, although some species have been introduced to the Southern Hemisphere.-Taxonomy:The genus...
, an infrageneric (a taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
level below genus) grouping of species characterized by a cinnamon-brown spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
, and pores less than 1 mm wide. Molecular phylogenetic analyses of ribosomal DNA
Ribosomal DNA
Ribosomal DNA codes for ribosomal RNA. The ribosome is an intracellular macromolecule that produces proteins or polypeptide chains. The ribosome itself consists of a composite of proteins and RNA. As shown in the figure, rDNA consists of a tandem repeat of a unit segment, an operon, composed of...
sequences shows that the most closely related species to Suillus brevipes include S. luteus
Suillus luteus
Suillus luteus is a basidiomycete fungus, and the type species of the genus Suillus. It is a common fungus indigenous to coniferous forests of Eurasia and North America, and introduced to southern Australia and New Zealand...
, S. pseudobrevipes
Suillus pseudobrevipes
Suillus pseudobrevipes is a species of edible mushroom in the genus Suillus. It was first described scientifically by American mycologists Harry D. Thiers and Alexander H. Smith in 1964....
, and S. weaverae (formerly Fuscoboletinus weaverae).
The specific epithet is derived from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
brevipes, meaning "short-footed". The mushroom is commonly known
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...
as the "stubby-stalk" or the "short-stemmed slippery Jack".
Description
The 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...
is deep brown to reddish-brown, later fading to tan
Tan (color)
Tan is a pale whiteish, tawny shade of white. The name is derived from tannum used in the tanning of leather.The first recorded use of tan as a shade name in English was in the year 1590....
with age, and it does not bruise with handling. The cap surface is smooth, and, depending on the moisture in the environment, may range from sticky to the touch to slimy. Depending on its maturity, the cap shape may range from spherical to broadly convex. The cap is medium sized, 5 – wide, and the cap cuticle
Pileipellis
thumb|300px||right|The cuticle of some mushrooms, such as [[Russula mustelina]] shown here, can be peeled from the cap, and may be useful as an identification feature....
can be peeled from the surface. The tubes are yellow, becoming olive-green with age, and they have an attachment to the stem that ranges from adnate (with most of the tube fused to the stem) to decurrent
Decurrent
Decurrent is a term used in botany and mycology to describe plant or fungal parts that extend downward.In botany, the term is most often applied to leaf blades that partly wrap or have wings around the stem or petiole and extend down along the stem...
(with the tubes broadly attached, but running somewhat down the length of the stem). They are typically up to 1 cm (0.393700787401575 in) deep, and there are about 1–2 tube mouths (pores) per millimeter. The pores are pale yellow, round, 1–2 mm wide, and do not change color when bruised.
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...
is white to pale yellow, dry, solid, not bruising, and pruinose (having a very fine whitish powder on the surface). A characteristic feature of many Suillus species are the glandular dots found on the stem—clumps of hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
l cell ends through which the fungus secretes various metabolic wastes, leaving a sticky or resinous "dot". In S. brevipes, the form of the glandular dots is variable: they may be absent, slightly underdeveloped or obscurely formed with age. The stem is usually short in comparison to the diameter of the cap, typically 2 – long and 1 – thick. It is either of equal width throughout, or may taper downwards; its surface bears minute puncture holes at maturity, and is it slightly fibrous at the base. The flesh
Trama (mycology)
In mycology trama is a term for the inner, fleshy portion of a mushroom's basidiocarp, or fruit body. It is distinct from the outer layer of tissue, known as the pileipellis or cuticle, and from the spore-bearing tissue layer known as the hymenium....
of the mushroom is initially white, but turns pale yellow in age. The odor and taste are mild. The spore print
Spore print
thumb|300px|right|Making a spore print of the mushroom Volvariella volvacea shown in composite: mushroom cap laid on white and dark paper; cap removed after 24 hours showing pinkish-tan spore print...
is cinnamon-brown.
Microscopic characteristics
The sporesBasidiospore
A basidiospore is a reproductive spore produced by Basidiomycete fungi. Basidiospores typically each contain one haploid nucleus that is the product of meiosis, and they are produced by specialized fungal cells called basidia. In grills under a cap of one common species in the phylum of...
are elliptical to oblong, smooth, and have dimensions of 7–10 by 3–4 µm
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...
. The spore-bearing cells, the basidia, are thin-walled, club-shaped to roughly cylindrical, and measure 2–25 by 5–7 µm. They bear either two or four spores. The pleurocystidia (cystidia that are found on the face of a gill) are roughly cylindrical with rounded ends, thin-walled, and 40–55 by 5–8 µm. The cells often have brown contents, and in the presence of 2% potassium hydroxide
Potassium hydroxide
Potassium hydroxide is an inorganic compound with the formula KOH, commonly called caustic potash.Along with sodium hydroxide , this colorless solid is a prototypical strong base. It has many industrial and niche applications. Most applications exploit its reactivity toward acids and its corrosive...
(KOH) will appear hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
(translucent) or vinaceous (red wine-colored); in Melzer's reagent
Melzer's Reagent
Melzer's reagent is a chemical reagent used by mycologists to assist with the identification of fungi.-Composition:...
they become pale yellow or brown. The cheilocystidia (cystidia found on the edge of a gill) are 30–60 by 7–10 µm, club-shaped to almost cylindrical, thin-walled, with brown incrusting material at the base, and arranged like a bundle of fibers. In KOH they appear hyaline, and are pale yellow in Melzer's reagent. Caulocystidia (found on the stem) are 60–90 by 7–9 µm, mostly cylindrical with rounded ends, and arranged in bundles with brown pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
particles at the base. The caulocystidia stain vinaceous in KOH. The cuticle
Pileipellis
thumb|300px||right|The cuticle of some mushrooms, such as [[Russula mustelina]] shown here, can be peeled from the cap, and may be useful as an identification feature....
of the cap is made of a layer of interwoven gelatinous hyphae that are individually 2–5 µm thick; the gelatinous hyphae are responsible for the sliminess of the cuticle. There are no clamp connection
Clamp connection
A clamp connection is a structure formed by growing hyphal cells of certain fungi. It is created to ensure each septum, or segment of hypha separated by crossed walls, receives a set of differing nuclei, which are obtained through mating of hyphae of differing sexual types...
s in the hypha
Hypha
A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...
e.
Edibility
Like many species of the genus SuillusSuillus
Suillus is a genus of basidiomycete fungi in the family Suillaceae and order Boletales. Species in the genus are associated with coniferous trees, and are mostly distributed in northern temperate locations, although some species have been introduced to the Southern Hemisphere.-Taxonomy:The genus...
, S. brevipes is edible
Edible mushroom
Edible mushrooms are the fleshy and edible fruiting bodies of several species of fungi. Mushrooms belong to the macrofungi, because their fruiting structures are large enough to be seen with the naked eye. They can appear either below ground or above ground where they may be picked by hand...
, and the mushroom is considered choice by some. The odor is mild, and the taste mild or slightly acidic. Field guide
Field guide
A field guide is a book designed to help the reader identify wildlife or other objects of natural occurrence . It is generally designed to be brought into the 'field' or local area where such objects exist to help distinguish between similar objects...
s typically recommended to remove the slimy cap cuticle, and, in older specimens, the tube layer before consumption. The mushrooms are common in the diet of grizzly bear
Grizzly Bear
The grizzly bear , also known as the silvertip bear, the grizzly, or the North American brown bear, is a subspecies of brown bear that generally lives in the uplands of western North America...
s in Yellowstone National Park
Yellowstone National Park
Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...
.
The fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
composition of S. brevipes fruit bodies has been analyzed. The cap contained a higher lipid
Lipid
Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
content than the stem—18.4% of the dry weight
Dry matter
The dry matter is a measurement of the mass of something when completely dried.The dry matter of plant and animal material would be its solids, i.e. all its constituents excluding water. The dry matter of food would include carbohydrates, fats, proteins, vitamins, minerals, and antioxidants...
, compared to 12.4%. In the cap, linoleic acid
Linoleic acid
Linoleic acid is an unsaturated n-6 fatty acid. It is a colorless liquid at room temperature. In physiological literature, it has a lipid number of 18:2...
made up 50.7% of the total lipids (65.7% in the stem), oleic acid
Oleic acid
Oleic acid is a monounsaturated omega-9 fatty acid found in various animal and vegetable fats. It has the formula CH37CH=CH7COOH. It is an odorless, colourless oil, although commercial samples may be yellowish. The trans isomer of oleic acid is called elaidic acid...
was 29.9% (12.4% in the stem), followed by palmitic acid
Palmitic acid
Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is one of the most common saturated fatty acids found in animals and plants. Its molecular formula is CH314CO2H. As its name indicates, it is a major component of the oil from palm trees . Palmitate is a term for the salts and esters of...
at 10.5% (12.6% in the stem). Linoleic acid—a member of the group of essential fatty acid
Essential fatty acid
Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest because the body requires them for good health but cannot synthesize them...
s called omega-6 fatty acid
Omega-6 fatty acid
n−6 fatty acids are a family of unsaturated fatty acids that have in common a final carbon–carbon double bond in the n−6 position, that is, the sixth bond, counting from the methyl end.The biological effects of the n−6 fatty acids are largely mediated by their conversion to n-6 eicosanoids...
s—is an essential dietary requirement for humans.
Similar species
Several Suillus species which grow under pines could be confused with S. brevipes. S. granulatusSuillus granulatus
Suillus granulatus is a pored mushroom of the genus Suillus in the Suillaceae family. It is similar to the related S. luteus, but can be distinguished by its ringless stalk. Like S. luteus, it is an edible mushroom that often grows in a symbiosis with pine...
has a shorter stem, and distinct raised granules on the stem. S. brevipes is differentiated from S. albidipes by not having a cottony roll of velar tissue (derived from a partial veil
Partial veil
thumb|150px|right|Developmental stages of [[Agaricus campestris]] showing the role and evolution of a partial veilPartial veil is a mycological term used to describe a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics...
) at the margin when young. S. pallidiceps is by distinguished its pale yellow cap color; and S. albivelatus has a veil. S. pungens
Suillus pungens
Suillus pungens, commonly known as the pungent slippery Jack or the pungent Suillus, is a species of fungus in the genus Suillus. The fruit bodies of the fungus have slimy convex caps up to wide. The mushroom is characterized by the very distinct color changes that occur in the cap throughout...
has a characteristic pungent odor, compared to the mild smell of S. brevipes, and like S. granulatus, has glandular dots on the stem.
Ecology
Suillus brevipes is a mycorrhizaMycorrhiza
A mycorrhiza is a symbiotic association between a fungus and the roots of a vascular plant....
l fungus, and it develops a close symbiotic
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
association with the roots of various tree species, especially pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...
. The underground mycelia form a sheath around the tree rootlets, and the fungal hyphae penetrate between the cortical
Cortex (botany)
In botany, the cortex is the outer layer of the stem or root of a plant, bounded on the outside by the epidermis and on the inside by the endodermis. It is composed mostly of undifferentiated cells, usually large thin-walled parenchyma cells of the ground tissue system. The outer cortical cells...
cells of the root, forming ectomycorrhizae. In this way, the fungus can supply the tree with minerals, while the tree reciprocates by supplying carbohydrate
Carbohydrate
A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...
s created by photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
. In nature, it associates with two- and three-needle pines, especially lodgepole
Lodgepole Pine
Lodgepole Pine, Pinus contorta, also known as Shore Pine, is a common tree in western North America. Like all pines, it is evergreen.-Subspecies:...
and ponderosa pine
Ponderosa Pine
Pinus ponderosa, commonly known as the Ponderosa Pine, Bull Pine, Blackjack Pine, or Western Yellow Pine, is a widespread and variable pine native to western North America. It was first described by David Douglas in 1826, from eastern Washington near present-day Spokane...
. Under controlled laboratory conditions, the fungus has been shown to form ectomycorrhizae with ponderosa, lodgepole, loblolly
Loblolly Pine
Pinus taeda is one of several pines native to the Southeastern United States, from central Texas east to Florida, and north to Delaware. It is particularly dominant in the eastern half of North Carolina, where there are huge expanses consisting solely of Loblolly Pine trees...
, eastern white
Eastern White Pine
Pinus strobus, commonly known as the eastern white pine, is a large pine native to eastern North America, occurring from Newfoundland west to Minnesota and southeastern Manitoba, and south along the Appalachian Mountains to the northern edge of Georgia.It is occasionally known as simply white pine,...
, patula, pond
Pond Pine
Pinus serotina is a tree found along the Atlantic coastal plain of the eastern United States, from southern New Jersey south to Florida and west to southern Alabama...
, radiata, and red pine
Red Pine
Pinus resinosa, commonly known as the red pine or Norway pine, is pine native to North America. The Red Pine occurs from Newfoundland west to Manitoba, and south to Pennsylvania, with several smaller, disjunct populations occurring in the Appalachian Mountains in Virginia and West Virginia, as well...
s. In vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
mycorrhizal associations formed with non-pine species include Pacific madrone
Pacific Madrone
Arbutus menziesii, commonly known as the Pacific Madrone, is a species of Arbutus found on the west coast of North America, from British Columbia to California...
, bearberry
Arctostaphylos uva-ursi
Arctostaphylos uva-ursi, with names for this species including Kinnikinnick and Pinemat manzanita, one of several related species referred to as Bearberry...
, western larch
Western Larch
Western Larch is a species of larch native to the mountains of western North America, in Canada in southeastern British Columbia and southwestern Alberta, and in the United States in eastern Washington, eastern Oregon, northern Idaho and western Montana.It is a large deciduous coniferous tree...
, Sitka spruce
Sitka Spruce
Picea sitchensis, the Sitka Spruce, is a large coniferous evergreen tree growing to 50–70 m tall, exceptionally to 95 m tall, and with a trunk diameter of up to 5 m, exceptionally to 6–7 m diameter...
, and coast Douglas-fir
Coast Douglas-fir
Pseudotsuga menziesii, known as Douglas-fir, Oregon Pine, or Douglas spruce, is an evergreen conifer species native to western North America. Its variety Pseudotsuga menziesii var. menziesii, also known as coast Douglas-fir grows in the coastal regions, from west-central British Columbia, Canada...
. Fungal growth is inhibited by the presence of high levels of the heavy metals cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
(350 ppm), lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
(200 ppm), and nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
(20 ppm).
During the regrowth of pine trees after disturbance like clearcutting
Clearcutting
Clearcutting, or clearfelling, is a controversial forestry/logging practice in which most or all trees in an area are uniformly cut down. Clearcutting, along with shelterwood and seed tree harvests, is used by foresters to create certain types of forest ecosystems and to promote select species that...
or wildfire
Wildfire
A wildfire is any uncontrolled fire in combustible vegetation that occurs in the countryside or a wilderness area. Other names such as brush fire, bushfire, forest fire, desert fire, grass fire, hill fire, squirrel fire, vegetation fire, veldfire, and wilkjjofire may be used to describe the same...
, there appears an orderly sequence of mycorrhizal fungi as one species is replaced by another. A study on the ecological succession
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
of ectomycorrhizal fungi in Canadian jack pine
Jack Pine
Jack pine is a North American pine with its native range in Canada east of the Rocky Mountains from Northwest Territories to Nova Scotia, and the northeast of the United States from Minnesota to Maine, with the southernmost part of the range just into northwest Indiana...
forests following wildfire concluded that S. brevipes is a multi-stage fungus. It appears relatively early during tree development; fruit bodies were common in 6-year old tree stands, and the fungus colonized the highest proportion of root tips. The fungus persists throughout the life of the tree, having been found in tree stands that were 41, 65, and 122 years old. There is, however, a relative reduction in the prevalence of the fungus with increasing stand age, which may be attributed to increased competition from other fungi, and a change in habitat brought about by closure of the forest canopy. Generally, S. brevipes responds favorably to silvicultural
Silviculture
Silviculture is the practice of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values. The name comes from the Latin silvi- + culture...
practices such as thinning and clearcutting. A 1996 study demonstrated that fruit bodies increased in abundance as the severity of disturbance increased. It has been suggested that the thick-walled, wiry rhizomorphs produced by the fungus may serve as an adaptation that helps it to survive and remain viable for a period of time following disturbance.
Habitat and distribution
Suillus brevipes grows singly, scattered, or in groups on the ground in late summer and autumn. A common—and sometimes abundant—mushroom, it occurs over most of North America (including Hawaii), south to Mexico, and north to Canada. This species has been found in Puerto RicoPuerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
growing under planted Pinus caribaea, where it is thought to have been introduced
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
inadvertently from North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
by the USDA Forest Service in 1955. Other introductions have also occurred in exotic pine plantations in Argentina, India, New Zealand, Japan, and Taiwan.