Key to genera of Boletes in the Pacific Northwest
Key to species of Boletus, Chalciporus, Gyroporus, and Porphyrellus
Description of Pulveruloboletus ravenelii
Three very useful books have been published since the original key was written: 1) The Boletes of North America A Compendium by Ernst E. Both which is primarily a nomenclatural guide, 2) North American Boletes by Alan E. Bessette, William C. Roody, and Arleen R. Bessette, which is a comprehensive illustrated guide, and 3) Mushrooms of the Redwood Coast, by Noah Siegel and Christian Schwarz.
Comments are included from Both’s work where relevant.
North American Boletes has been used extensively by bolete enthusiasts - its names were followed in general at first, but later there were extensive changes to Boletus names as a result of molecular studies.
Mushrooms of the Redwood Coast has very useful information for the west coast of North America and excellent photographs
The following species were added to the original key: Buchwaldoboletus sphaerocephalus, Caloboletus marshii, Chalciporus piperatoides, Pulveroboletus ravenelii, Rubroboletus eastwoodiae, Rubroboletus haematinus, Xerocomellus dryophilus, Xerocomellus rainisiae, Gastroboletus imbellus, Gastroboletus ruber, Gastroboletus vividus, Gyroporus castaneus, Leccinum atrostipitatum, Leccinum holopus, Leccinum testaceoscabrum, Suillus fuscotomentosus, and Suillus placidus. Name changes were as follows: Boletus amylosporus replaced Tylopilus amylosporus, Boletus luridiformis replaced B. erythropus, Boletus regineus replaced Boletus aereus, Boletus rex-veris replaced B. pinicola and B. pinophilus, Suillus viscidus replaced Fuscoboletinus aeruginascens, Suillus flavidus replaced S. umbonatus, and Suillus neoalbidipes replaced S. albidipes. Boletus was segregated into different genera and these changes are discussed under GENERA SEGREGATED FROM BOLETUS IN P.N.W.
The following species have been deleted because their species status or Pacific Northwest distribution is not agreed on by modern authors: Boletus fragrans Vittadini, Boletus porosporus (Imler) Watling var. americanus A.H. Sm. & Thiers, Leccinum incarnatum A.H. Sm., Thiers & Watling, Leccinum subfulvum A.H. Sm., Thiers & Watling, Leccinum truebloodii A.H. Sm., Thiers & Watling, Suillus appendiculatus (Peck) A.H. Sm. & Thiers, and Suillus ruber Singer & Sipe. For reference, note is made in the key where they would appear, with a reference to the description in the appendix on Excluded Species.
The molecular study of Nguyen et al.(2016) suggests a number of name changes in Suillus.
They considered
Suillus borealis a synonym of | Suillus brunnescens |
Suillus neoalbidipes a synonym of | Suillus glandulosipes |
Their research supported the earlier conclusion (Klofac(2013)) that
Suillus sibiricus is a synonym of | Suillus americanus |
Their phylogenetic tree also suggests
Suillus helenae may be a synonym of | Suillus flavidus |
Suillus imitatus may be a synonym of | Suillus caerulescens |
Suillus subolivaceus may be a synonym of | Suillus acidus |
Their suggested changes had not been applied as of August 14, 2019 to current names listed in the online Species Fungorum and MycoBank and we have not yet applied them here, but the function of those databases is nomenclatural not taxonomic and there is no obligation to update promptly the current names that they list. The following suggested changes have not been implemented in this key yet either.
Nguyen et al. also proposed usage if different names for North American collections known under European names. (The names Fuscoboletinus laricinus and F. aeruginascens are synonyms of Suillus viscidus.)
Suillus cavipes should be replaced by | Suillus ampliporus |
Suillus granulatus should be replaced by | Suillus weaverae |
Suillus grevillei should be replaced by | Suillus clintonianus |
Suillus viscidus should be replaced by | Suillus elbensis |
Of the many divisions of the large Friesian genus Boletus since 1821, the classification system of Dr. A. H. Smith and Dr. H. D. Thiers is used here because theirs embraces the greatest amount of published material on species growing in the Pacific Northwest. Only the genera and species known to occur here are included in this regional key. No doubt many others will be found and require further description and additional changes in the key.
For the most part descriptions have been adapted from How to Know the Non-gilled Fleshy Fungi by Drs. Helen V. and Alexander H. Smith; A Contribution toward a monograph of North American Species of Suillus by Drs. A. H. Smith and Harry D. Thiers, and California Mushrooms: A Field Guide to the Boletes by Dr. Harry D. Thiers.
* Known to be choice edibles
% Rare species!! Please bring in and take to bolete specialist if possible.
# Poisonous
Because many boletes vary considerably in color and surface texture due to weather conditions, a few species are being included in more than one place in the key. Any part with a gelatinous layer - cap cuticle, subcutis, or veil - can thus range from dry to glutinous. Accordingly, descriptions will have to be mentally revised to suit the weather. Spore measurements vary little and are therefore of little help in separating species. This is a trial key.
Sincere appreciation is hereby expressed for personal help and access to both published and unpublished data by Dr. Helen V. Smith, Dr. A. H. Smith, Dr. Harry D. Thiers, Dr. Daniel E. Stuntz, Dr. Roy Watling, and Dr. Orson K. Miller Jr.
1a Tubes usually irregular and not vertical; spore deposit not obtainable; fruitbodies +/- aborted-looking (rare)
................................................................................Gastroboletus
1b Tubes usually regular and vertical; spore deposit obtainable; fruitbodies with normal caps and stems
................................................................................2
2a Bright yellow powdery cap and lower stem
................................................................................Pulveroboletus
2b Not with bright yellow powdery cap and lower stem
................................................................................3
3a Stem roughened by tufted fibrillose scales which darken to brownish or black by maturity
................................................................................Leccinum
3a Stem smooth or ornamented but not as above
................................................................................4
4a Button cap with partial veil or cottony roll, OR mature stem with an annulus or annular zone, OR mature stem with a granular rash of raised dark spots
................................................................................(part of) Suillus
(Spore print olive, dull yellow, etc. = Suillus. Spore print reddish brown or purplish brown, pores large and angular, tubes decurrent, only under larch = Fuscoboletinus in Suillus key.)
4b Button caps and mature stems lacking ornamentation described above
................................................................................5
5a Stem bearing a network of raised fibrils in a fishnet pattern ("reticulate")
................................................................................(part of) Boletus
5a Stem lacking such a network, more or less smooth
................................................................................6
6a Spore print and mature pores with reddish tint (reddish brown or chocolate brown)
................................................................................Porphyrellus and Tylopilus
6b Spore print with more olive or dingy yellow tints
................................................................................7
7a Cap not viscid, usually suedelike and often cracking, occasionally glabrous
................................................................................Boletus, Chalciporus, Gyroporus
7b Cap viscid to glutinous, especially young (also see B. flaviporus in Boletus key)
................................................................................(part of) Suillus
Additional probabilities if stem is plain:
Stem red = Boletus |
Cap cracking =Boletus |
Stem olive = Boletus |
Cap glutinous = Suillus |
Stem white = Suillus |
Pores chocolate or red-brown = Porphyrellus |
Boletus (porcini) in the strict sense are Boletus edulis and its relatives, which have large dense fruitbodies, small pores that are white or light creamy yellowish when young, and club-shaped, reticulate stems. Some species still have Boletus names but need to be placed in other genera.
Butyriboletus (butter boletes) have large dense fruitbodies and reticulate stems like the porcini, but differ in yellow pores that turn blue, and yellow flesh that may turn blue.
Caloboletus (bitter boletes) have sour-bitter flavour, and blue-bruising reactions of pores and flesh.
Xerocomellus (cracking boletes) have brown to dark gray to purplish black to pinkish caps that often crack, yellow pores that often turn blue, and reddish to reddish-and-yellow stems.
Xerocomus (brown velvet boletes) have dry, velvety, brownish caps, rather coarse yellowish pores that stain blue, and stem colors that include yellow, rusty, and pallid, but not bright red.
Chalciporus (peppery boletes) have small fruitbodies, yellow to orange-brown pores that often bruise darker brown or blue, peppery taste, and yellow mycelium at stem base.
Rubroboletus (and Suillellus) (red-pored boletes) have bright red to dark red pores that turn blue when bruised, and club-shaped stems.
Buchwaldoboletus (wood-loving boletes) have reddish brown to yellow caps, yellow pores that turn blue, yellow flesh that may turn blue, and growth on or near wood.
Pulveroboletus raveneli (powdery sulphur bolete) has medium to large fruitbody, brilliant yellow cap, bright yellow pores that stain blue, and growth on the ground.
Aureoboletus flaviporus (viscid yellow-pored bolete) has medium to large fruitbody, cinnamon to reddish brown, viscid cap, yellow pores that do not turn blue, acid taste.
SPECIES NAME | SPECIES FUNGORUM | MYCOBANK | OTHER |
abieticola | Butyriboletus abieticola | homotypic synonyms | |
amygdalinus | Suillellus amygdalinus | Suillellus amygdalinus | |
amylosporus | Boletus | Boletus | probably Xerocomellus |
‘appendiculatus’ | Butyriboletus persolidus | Butyriboletus persolidus | (California) |
barrowsii | Boletus | Boletus | |
‘calopus’ | Caloboletus ‘calopus’ | Caloboletus ‘calopus’ | |
‘chrysenteron’ | Xerocomellus ‘chrysenteron’ | Xerocomellus ‘chrysenteron’ | Xerocomellus diffractus nom. prov. |
coccyginus | Boletus | Boletus | (needs a different genus) |
coniferarum | Caloboletus conifericola | Caloboletus conifericola | |
dryophilus | Xerocomellus dryophilus | Xerocomellus dryophilus | |
edulis | Boletus | Boletus | |
fibrillosus | Boletus | Boletus | |
flaviporus | Aureoboletus flaviporus | Aureoboletus flaviporus | |
haematinus | Rubroboletus haematinus | Rubroboletus haematinus | |
‘luridiformis’ | Sutorius ‘luridiformis’ | Sutorius ‘luridiformis’ | Neoboletus ‘luridiformis’ preferred |
marshii | Caloboletus marshii | Caloboletus marshii | |
mirabilis | Aureoboletus mirabilis | Aureoboletus mirabilis | may need different genus |
mottiae | Boletus | Boletus | |
oregonensis | Boletus | Boletus | Xerocomus oregonensis comb. prov. |
pulcherrimus | Rubroboletus pulcherrimus | Rubroboletus pulcherrimus | eastwoodiae a misapplied name |
pulverulentus | Cyanoboletus pulverulentus | Cyanoboletus pulverulentus | |
radicans | Caloboletus radicans | Caloboletus radicans | |
rainisiae | Cyanoboletus rainisiae | Cyanoboletus rainisiae | Xerocomellus rainisiae preferred |
ravenelii | Pulveroboletus ravenelii | homotypic synonyms | |
regineus | Boletus | Boletus | |
‘regius’ | Butyriboletus autumniregius, Butyriboletus primiregius, Butyriboletus querciregius | Butyriboletus autumniregius, Butyriboletus primiregius, Butyriboletus querciregius | |
rex-veris | Boletus | Boletus | |
rubripes | Caloboletus rubripes | Caloboletus rubripes | |
‘satanas’ | Rubroboletus eastwoodiae | Rubroboletus eastwoodiae | |
smithii | Boletus | Boletus | (needs a different genus) |
‘spadiceus’ | Boletus ‘ferrugineus’ | Xerocomus ‘ferrugineus’ | (correct name unclear) |
speciosus | Boletus | Boletus | likely Butyriboletus speciosus |
sphaerocephalus | Buchwaldoboletus sphaerocephalus | Buchwaldoboletus sphaerocephalus | |
subglabripes | Hemileccinum subglabripes | Hemileccinum subglabripes | |
subtomentosus | Boletus subtomentosus | Xerocomus subtomentosus | Xerocomus subtomentosus preferred |
‘truncatus’ | Xerocomellus ‘truncatus’ | Xerocomus ‘truncatus’ | |
variipes | Boletus | Boletus | |
zelleri | Xerocomellus zelleri | Xerocomellus zelleri |
NOTES ON NAME UPDATE
Molecular research has been responsible for many published name changes, but the set of names for Boletus species continues to change with ongoing research. Names are those given as the current names in the online Species Fungorum and online MycoBank service. In some cases MycoBank does not designate a current name but instead gives both the Boletus name and the new name as homotypic or obligate synonyms. The two services are nomenclatural not taxonomic resources. Their primary aim is to list published names in an accessible way, not to determine the current name.
Single quotation marks are placed around names in the key that are thought to be misapplied. This means that a species by that name exists somewhere, but it is not the one that we know in the Pacific Northwest by that name. The following deserve a further explanation.
The following species are not located in the main key:
1a Stem with a network of raised fibrils (= reticulate)
................................................................................2
1b Stem lacking such a network
................................................................................21
2a Pores dark red; cap brown to gray; bluing on injury
................................................................................3
2b Pores another color - usually white, yellow, or olivaceous
................................................................................5
3a Abruptly bulbous stipe when mature; associated with oak; cap light gray to olive buff with pink tones
................................................................................# Rubroboletus eastwoodiae
(Boletus satanas Lenz and Boletus satanus are misapplied names.)
3b Stipe not abruptly bulbous when mature; in coniferous or mixed forest; cap reddish brown, pale brown, olive-brown, or yellow-brown, may have pink tones
................................................................................4
4a Cap reddish brown to olive-brown, or with grayish fibrils on reddish ground color, pores dark red at first, becoming orange-red, then brownish red, often yellow near margin; stipe club-shaped but no abrupt bulb, sometimes equal, reddish brown with dark red reticulation; growing in conifers and mixed woods
................................................................................# Rubroboletus pulcherrimus
(Also known as Boletus pulcherrimus. This species has passed in California under the name B. eastwoodiae, but the type of B. eastwoodiae (Murrill) Sacc. & Trotter is another species similar but not identical to B. satanus Lenz.)
4b Cap light brown to yellow-brown or olive-brown, often tinged red; pores yellow when very young, soon becoming red except near margin; stipe sometimes bulbous but not abruptly, becoming equal, stipe yellow with pale red reticulation; associated with conifers, especially red fir
................................................................................# Rubroboletus haematinus
(also known as Boletus haematinus.
5a Growing on wood (see description under 26a)
................................................................................* B. mirabilis
5b Not growing on wood
................................................................................6
6a Cap bright red or rosy red (for reddish brown caps, take next choice)
................................................................................7
6b Cap not bright red or rosy red
................................................................................8
7a Flesh and pores staining blue readily; stem equal or subequal
................................................................................% Boletus speciosus
CAP deep rose red in all stages; 8-15 cm wide; dry and suede-like; flesh yellowish, quickly blue when cut. TASTE and ODOR mild. TUBES and PORES yellow, darkening with age; quickly blue when cut. STEM light yellow with red at base; 5-13 cm x 1/5-4 cm thick, at base enlarged or pinched off; surface finely reticulate. HABITAT only with oaks?. DISTRIBUTION most reports are from eastern North America, but collected from Chelan Co. Washington by D. Stuntz. EDIBILITY unknown. MICROSTRUCTURES spores 10-15 x 3.5-4.5 um; pileus cuticle a trichodermium collapsing to form a matted layer.
7b Flesh and pores staining blue only slightly; young stem swollen
................................................................................% Butyriboletus autumniregius, Butyriboletus primiregius, Butyriboletus querciregius
8a Tubes and pores yellow, not bluing on injury, cap red brown and viscid
................................................................................% Aureoboletus flaviporus
(See 36a for description.)
8b Tubes and pores white or yellow when young, bluing or not, (if yellow and not bluing then cap dry)
................................................................................9
9a Tubes and pores white when young, no part bluing on injury
................................................................................10
9b Tubes and pores yellow when young, mostly bluing on injury
................................................................................15
10a Cap milk chocolate brown or darker, or cap distinctly wrinkled-reticulate (raised wrinkled-netted pattern)
................................................................................11
10b Cap not milk chocolate brown or darker, and cap not distinctly wrinkled-reticulate
................................................................................12
11a Only under oaks and madrone; cap almost black with smooth to pitted surface, dry to moist (subviscid only when old); (spores 12-13.5 um long)
................................................................................* Boletus regineus
11b Under conifers; cap dark brown with fibrils in wrinkled netted pattern, moist to subviscid, (spores 14.3-17.1 um long)
................................................................................Boletus mottiae
(also called Boletus mottii which is grammatically incorrect since its collector Lillian Mott is a woman.)
CAP cinnamon brown on disc, more buff toward margin; 6-12 cm; wrinkled-reticulate from bunched fibrils, hence uneven; moist to subviscid; flesh soft, white, unchanging when exposed. TASTE and ODOR not distinctive. TUBES and PORES white when young, aging yellow; unchanging when bruised. STEM buff to cinnamon brown, with fine overlying reticulation of same color; 5-7.5 cm long x 1.5-3 cm thick, may be thicker at base. HABITAT under conifers. DISTRIBUTION Washington, Oregon, California, appears on an Idaho foray list. EDIBILITY unknown, but probably edible, since it seems to be closely allied to the B. edulis complex. MICROSTRUCTURES spores 14.3-17.1 x 3.8-5 um, pileus cuticle subgelatinous.
12a (10b) Only under oaks; cap gray-brown
................................................................................% Boletus variipes
CAP blackish brown to smoky brown or crust brown; 6-20 cm; dry, suedelike or scaly, usually becoming strongly areolate (mud-cracked) in age; flesh white, unchanging. TASTE and ODOR mild. TUBES and PORES white when young, pores "stuffed", soon yellow but unchanging if injured. STEM colored like cap or paler; 8-15 cm long x 1-3.5 cm thick; finely reticulate; naked to granular or fibrillose; mycelium white. HABITAT under oaks and other hardwoods. DISTRIBUTION "eastern Canada south to North Carolina and Texas, west to the Great Lakes region, distribution limits yet to be established", (Bessette et al.), included in Kit Scates 1982 key: further distribution records are desirable. EDIBILITY edible. MICROSTRUCTURES spores 10-18 x 3.5-5 um; hyphal walls of cap cuticle smooth.
12b Under pines mostly; cap colors varied
................................................................................13
13a Cap almost white
................................................................................% Boletus barrowsii
13b Cap with more color
................................................................................14
14a Cap red-brown; common east of Cascade Mt. Summit
................................................................................* Boletus rex-veris
(formerly known as Boletus pinicola (Vittad.) Venturi or Boletus pinophilus Pilát & Dermek)
14b Cap pallid to tan; widespread
................................................................................* Boletus edulis
15a (9b) Taste noticeably bitter
................................................................................16
15b Taste not noticeably bitter
................................................................................18
16a Stem swollen and/or with red color
................................................................................Caloboletus calopus
(also known as Boletus calopus)
16b Stem thick but not very swollen, with little or no bright red color
................................................................................17
17a Stem base with root-like projection; stem tan
................................................................................% Caloboletus radicans
(also known as Boletus radicans)
CAP tan, yellowish on margin, rarely with olive or reddish tones; usually up to 16 cm but perhaps up to 20 or even 30 cm wide; surface dry, glabrous to +/- tomentose and cracking; flesh whitish, bluing. TASTE bitter to very bitter. ODOR mild to slightly fragrant. TUBES and PORES yellow aging dirty tan yellow, bluing promptly on injury; spores small (possibly medium in very large specimens), round. STEM variable - reticulate (very fine, lens often necessary) or not, can be glabrous, granular, or striate; color usually yellow at apex varying to brown mottled with other colors below, sometimes with reddish or brownish ring-zones; 5-12 cm long x 1-5 cm thick, subequal to subbulbous, 1-3 cm at base within the ground, perhaps tapered; bluing on injury; mycelium pale yellow. HABITAT variable. EDIBILITY not poisonous, but too bitter to be good. MICROSTRUCTURES spores 9-16 x 4-5.5 um. DISTRIBUTION The occurrence of Boletus radicans Pers. sensu Kallenbach in North America is questionable because of confusion with B. inedulis (Murrill) Murrill, according to Bessette et al. It was reported from Washington (Janet Lindgren 1996, pers. comm.) and was included in the 1982 key with the statement "This is a confused species concept, and its presence needs confirmation". Most reports of the species are from eastern North America.
17b Stem base not rooting; stem pale yellow to olive to brown
................................................................................Caloboletus conifericola
(Also known as Boletus coniferarum which is an invalid name)
18a (15b) Cap olive to yellow-brown, reddish brown, or date-brown; surface velvety-subtomentose (velvety to somewhat woolly)
................................................................................B. spadiceus
(See 42b for description.)
(also known as Xerocomus spadiceus (Fr.) Quélet, but correct genus unclear)
18b Cap some shade of brown or pale rose color, or cap almost bald, or cap fibrillose to scaly
................................................................................19
19a Cap almost glabrous (bald); only under hardwoods; reddish brown to rusty brown or yellow-brown or with rusty spots
................................................................................% Butyriboletus persolidus
Boletus appendiculatus is a misapplied name.
19b Cap fibrillose to scaly, under conifers
................................................................................20
20a Cap dark brown to chestnut brown, fibrillose, mostly coastal areas
................................................................................% Boletus fibrillosus
20b Cap blotchy pale rose, fibrillose-scaly; with true firs above 5000 feet
................................................................................Butyriboletus abieticola
(also known as Boletus abieticola)
CAP light rose, with tan spots; 9-13 cm; fibrillose when young to fibrillose-scaly in age; dry; flesh only occasionally changing to blue when exposed. TASTE and ODOR mild. TUBES and PORES yellow, darkening with age, changing to blue when bruised or exposed; pores small, angular. STEM yellow except reddish base; dry, yellow-reticulate; 9-12 cm long x 4-5 cm at apex and 5-6 cm below. HABITAT associated with true firs at high elevations (above 5000 feet). DISTRIBUTION Washington, California, reported from Oregon and Montana. EDIBILITY edible. MICROSTRUCTURES spores 14-17.5 x 4.5-5.5 um; pileus cuticle a tangled trichodermium with spiral encrustations, hyphae stain reddish in Melzer’s.
21a (1b) Pores cinnamon (if so, taste peppery), or red or pinkish
................................................................................22
21b Pores yellow, olive, brown, or whitish
................................................................................25
22a Pores cinnamon; taste peppery; stem slim, yellow at base
................................................................................23
22b Pores dark red, light red or pinkish
................................................................................24
23a Pore surface staining blackish blue to greenish blue when bruised, (spores 6-10 x 3-4 um)
................................................................................Chalciporus piperatoides
(also known as Boletus piperatoides A.H. Sm. & Thiers)
(See also 33a.)
CAP buff to yellow-brown, orange-brown or rusty brown; small to medium 3-8 cm wide, dry but viscid when moist; smooth or nearly so; flesh pale pinkish buff to dull pinkish brown or dull yellow-brown; typically bluing when cut, at least above the tubes. TASTE slowly peppery. ODOR not distinctive. PORES dull yellow at first, becoming yellow-brown to orange-brown, dull cinnamon or brown, often with an olive tinge; staining blue to bluish black when bruised; irregular in shape. STEM colored like cap or paler, basal mycelium bright yellow; dry, fibrillose-punctate to fibrous-striate; 3-8 cm x 0.5-1.6 cm; stem flesh yellow. HABITAT under conifers or hardwoods. DISTRIBUTION at least Washington Oregon, California, reported from British Columbia. EDIBILITY unknown, but likely too peppery. MICROSTRUCTURES spores 6-10 x 3-4 um, hymenophoral trama not amyloid. | Chalciporus piperatoides Michael Wood (MykoWeb) |
23b Pore surface not staining blue, (spores 9-12 x 4-5 um)
................................................................................Chalciporus piperatus
(also known as Boletus piperatus Bull.)
(See also 32b.)
24a (22b) Cap brown to red-brown; habitat various; pores dark red
................................................................................Boletus luridiformis
(Likely a Neoboletus rather than a Sutorius. lso known as Boletus erythropus (Fr.) Krombholz)
24b Cap pink, red, or winey; typically under oak and manzanita, but also under redwoods; pores red to dull rusty red
................................................................................% Suillellus amygdalinus
(also known as Boletus amygdalinus)
25a (21b) Growing directly on rotting wood
................................................................................26
25b Not growing directly on rotting wood
................................................................................27
26a Cap brown and granular; single or in 2’s or 3’s
................................................................................* Boletus mirabilis
(also known as Aureoboletus mirabilis, but may not be the right genus))
(See also 5a.)
26b Caps bright yellow, smooth; often clustered
................................................................................% Buchwaldoboletus sphaerocephalus
(also known as Boletus sphaerocephalus)
CAP sulphur yellow when young, becoming pale yellow to whitish in age; 4-10 cm wide; dry, somewhat tomentose, often cracking in age; flesh sulphur yellow to pale yellow, typically bluing when exposed, but sometimes slowly or not at all. TASTE not distinctive or somewhat bitter. ODOR not distinctive. PORES yellow at first, becoming dull yellow to brownish yellow, bluing, then slowly staining brownish when bruised. STEM yellow, 5-10 cm x 1-3 cm, appressed fibrillose, with yellow basal mycelium. HABIT and HABITAT scattered, in groups or clusters in sawdust, or on stumps or the surrounding soil. DISTRIBUTION at least Idaho. EDIBILITY unknown. MICROSTRUCTURES spores 7-9 x 3-4 um. REMARKS Boletus hemichrysus Berkeley and Curtis, "considered to be a synonym by some authors, has a bright golden yellow to orange-yellow pileus, a red-brown to reddish brown pore surface, and a stipe tinged with red." (Bessette et al.)
27a (25b) Cap and stem instantly staining blue to bluish black or dark green to greenish black when bruised or handled, taste mild
................................................................................28
27b Cap and stem not instantly staining dark green to blue or greenish black when bruised or handled, or taste peppery
................................................................................29
28a Instantly staining green to greenish black when bruised, cap dark olive brown to blackish brown when young, becoming paler olive-brown to yellowish brown at maturity
................................................................................Xerocomellus rainisiae
(also known as Cyanoboletus rainisiae, Boletus rainisiae, Boletus rainisii)
CAP dark olive-brown to blackish brown when young, becoming paler olive-brown to yellowish brown, instantly staining greenish black when handled or bruised; 4-11.5cm wide; dry, velvety-tomentose to appressed-tomentose, becoming conspicuously cracked with yellow flesh between cracks in age; flesh yellow, instantly bluing when exposed. TASTE and ODOR not distinctive. PORES pale yellow, becoming darker dull golden yellow with brownish to reddish tints in age, instantly staining dark green, then slowly brownish when bruised. STEM bright yellow with rusty red tinges near the base, instantly staining dark green, then greenish black when handled or bruised; flesh yellow with dull red tints at base, instantly bluing when exposed; basal mycelium white; 3-9 cm x 1.5-3.5 cm, distinctly club-shaped at first, sometimes nearly equal at maturity, with pinched base, dry, bald without reticulation or raised longitudinal ridges. HABITAT under mixed conifers, including Douglas-fir and Western Hemlock. DISTRIBUTION Washington and possibly California. EDIBILITY unknown. MICROSTRUCTURES spores 10-17 x 4.2-7 um; basidia 37-55 x 9-14 um; pileus cuticle a trichodermium with narrowly clavate to fusiform cystidioid end-cells.
28b Instantly staining blue to blackish blue when bruised or handled, cap dark yellow-brown to blackish brown or dark cinnamon-brown, without olive tones
................................................................................Cyanoboletus pulverulentus
(also known as Xerocomus pulverulentus)
CAP dark yellow-brown to blackish brown or dark cinnamon-brown and often developing reddish tints in age, instantly staining blackish blue when bruised or handled; 4-12.5 cm wide; dry, subtomentose, becoming bald and often somewhat shiny in age; flesh yellow, instantly bluing on exposure. TASTE and ODOR not distinctive. PORES yellow when young, darkening to golden yellow to brownish yellow, instantly bluing, then slowly staining dull brown when bruised. STEM yellow in upper part and darker yellow to orange-yellow downward, typically reddish brown toward the base, quickly bluing, then slowly staining dull brown when handled; flesh reddish brown in the base, yellow in upper part, and instantly bluing when exposed, 3.5-9 cm x 1.5-3.5 cm, nearly equal or sometimes enlarged downward, dry, pruinose at apex and typically toward base, lacking reticulation but often with raised longitudinal ridges. HABITAT under conifers or hardwoods. DISTRIBUTION eastern Canada south to Florida west to at least Michigan. It has been reported from northern California, Idaho, Oregon, and Washington, but at least some may have been B. rainisii, which was not described till 2000. EDIBILITY edible. MICROSTRUCTURES spores 11-15 x 4-6 um; basidia 22-35 x 6-9 um; pileus cuticle a cutis of undifferentiated interwoven hyphae that measure 3-7 um wide.
29a (27b) Stem robust (more than 2.5 cm diameter)
................................................................................30
29b Stem average or slender (2.5 cm or less diameter)
................................................................................32
30a Found only under conifers at 6000 feet +; color olive to brown
................................................................................% Lanmaoa fragrans
(See Excluded Species.)
30b Not confined to high mountains; olive to buff when young, aging tan or red
................................................................................31
31a Cap tan without red; young stem yellow + red; taste bitter, conifer or mixed forest
................................................................................Caloboletus rubripes
(also known as Boletus rubripes)
31b Cap white tan without red; young stem yellow +/- red; taste bitter, under oak
................................................................................% Caloboletus marshii
CAP white to grayish white when young, aging buff or tan; 6-15(20) cm wide; faintly velvety and with a fine whitish bloom when young; flesh thick, pallid, bluing on exposure. TASTE bitter, at least latently. ODOR somewhat sour. TUBES and PORES yellow, staining blue when fresh, darkening with age. STEM yellow, sometimes with small reddish dots or splotches; changing to blue when exposed; 4-15 cm long x 2-5 cm at top, swollen or bulbous in lower part, often narrowed at base. HABITAT under oak. DISTRIBUTION Washington, Oregon, California. EDIBILITY not edible. MICROSTRUCTURES spores 11-14 x 4.5-6 um; cap cuticle an entangled upright layer of sinuous, cylindrical hyphae. REMARKS described in 2014.
31c Cap developing red tones with age; taste mild
................................................................................Boletus smithii
32a (29b) Basal mycelium bright yellow, taste peppery
................................................................................33
32b Basal mycelium not bright yellow or taste not peppery
................................................................................34
33a Pore surface staining blackish blue to greenish blue when bruised, (spores 6-10 x 3-4 um)
................................................................................Chalciporus piperatoides
(See 23a for description.)
33b Pore surface not staining blue, (spores 9-12 x 4-5 um)
................................................................................Chalciporus piperatus
(See 23b for description.)
34a (32b) Spore print red-brown to chocolate-brown or gray-brown
................................................................................35
34b Spore print yellow to olivaceous or olive-brown (When in doubt, use this.)
................................................................................36
35a Cap, pores and stem chocolate-brown (stem base often whitish)
................................................................................Porphyrellus porphyrosporus
35b Cap olive-brown to gray-brown; stem olive gray, typically reddish in places, tubes yellow
................................................................................Boletus amylosporus
CAP olive-brown to gray-brown; 4-12 cm, velvety, cracking; flesh yellow to dull whitish, +/- bluing, may be red under cap surface and around larval tunnels. TASTE and ODOR mild. TUBES and PORES yellow; mature pores large and irregular, readily bluing. STEM usually olive-gray, reddish in places or dots, not reticulate; 4-9 cm long, 1-1.5 cm thick; reddish inside. HABITAT under Red Alder or oak in the fall. DISTRIBUTION at least Idaho and California. EDIBILITY unknown. SPORE DEPOSIT dark reddish brown. MICROSTRUCTURES spores 12-17 x 4.5-6 um, truncate at apex (or notched), dextrinoid or weakly to distinctly amyloid.
36a (34b) Cap very viscid, red-brown; under oaks and other hardwoods
................................................................................% Aureoboletus flaviporus
(also known as Boletus flaviporus)
(See also 8a.)
36b Cap not viscid
................................................................................37
37a Cap almost black, rugose (bumpy-wrinkled) when young; stem red
................................................................................* Xerocomellu zelleri group
(also known as Xerocomus zelleri (Murrill) Snell)
37b Not combining features above
................................................................................38
38a Stem scurfy, yellow when young (like a yellow Leccinum), red when old; cap chestnut to yellowish brown; under birch; no part bluing
................................................................................% Hemileccinum subglabripes
(also known as Boletus subglabripes)
38c Not combining features above
................................................................................39
39a Cap +/- 5 cm wide, bright red granular, yellow background; not bluing
................................................................................% Boletus coccyginus
CAP bright rosy red when young, with age granular tomentose cuticle cracking to reveal yellow background; small (3-5 cm wide); flesh pale lemon yellow, not bluing on exposure. TUBES and PORES bright greenish yellow, sometimes slowly turning +/- greenish on cutting; pores large for such a small bolete. STEM pale yellow-buff with a little red at top; not reticulate; 4-7 cm x 0.5-1.0 cm; flesh slowly turning reddish-brown on cutting but not blue. HABITAT soil under conifers. DISTRIBUTION rare, known from only two locations in the Pacific Northwest, described from California. EDIBILITY unknown, but too small to be of much value. MICROSTRUCTURES 11.2-17.6 x 5.3-7 um; pileus cuticle a tangled trichodermium staining dark yellow in KOH, walls asperulate to faintly encrusted.
(also known as Boletus dryophilus)
CAP ruby-red, vinaceous red or brick red when fresh, with age more pinkish brown, cuticle usually cracking extensively to reveal whitish to pinkish background; flesh yellow, bruising quickly when cut. TASTE very bitter when fresh, milder when old. ODOR sour. TUBES and PORES pale yellow to lemon yellow or olive yellow, bruising blue readily. STEM yellow in upper part, downward becoming more cap-colored, the reddish pigmemnt sometimes appearing finely punctate. HABITAT soil in oak woods. DISTRIBUTION common in southern California but reaching as far north as the Columbia River valley (N. Siegel, pers. comm.). EDIBILITY said to be edible but even young ones parasitized by Hypomyces. SPORE DEPOSIT olive-brown. MICROSTRUCTURES 11.5-16 x 5-6.5 um.
39c ot combining these features
................................................................................40
40a Cap dry, chestnut brown to yellow-brown or orange-brown; flesh white, not staining when cut or bruised; pores whitish to buff or yellowish; stem with cavities or hollow, and colored like cap; spore deposit yellowish
................................................................................% Gyroporus castaneus
40b Not combining these features
................................................................................41
41a Cap cracking readily, even when young; tubes bluing readily on injury
................................................................................43
41b Cap +/- cracking with age or dry weather; bluing only slightly
................................................................................42
42a Cap tan, brown, or olive; cap slightly darker or red-brown with ammonia
................................................................................Xerocomus subtomentosus
(also known as Boletus subtomentosus )
42b Cap brown, sometimes red-brown; blue-green briefly then dark when ammonia is put on cap
................................................................................Boletus spadiceus
(also known as Xerocomus spadiceus)
(See also 18a.)
43a (41a) Spores not truncate
................................................................................Xerocomellus chrysenteron
(also known as Boletus chrysenteron)
CAP dark brown to olive gray; 6-8 cm wide; dull velvety cuticle cracking early and showing pallid flesh beneath which usually reddens with age; dry. TASTE mild to slightly acid and unpleasant. ODOR not distinctive. TUBES and PORES yellow, usually changing to blue when bruised; pores large (1-1.5 mm broad), very irregular. STEM usually yellow at top becoming rusty or reddish near base; dry, lacking ornamentation, except often longitudinally ridged or striate; 7-10 cm long x 1-1.7 cm thick at apex, equal to tapering slightly at the base. HABITAT in mixed forests. DISTRIBUTION British Columbia, Washington, Oregon, California, and reported from Idaho and Montana. EDIBILITY edible (but there are many close lookalikes). MICROSTRUCTURES spores 12-13.5 x 5-6 um; pileus cuticle staining dark cinnamon brown in KOH, a trichodermium with slightly differentiated (not inflated) hyphal tips, the hyphae often heavily and spirally encrusted. REMARKS Collections known under this name may constitute more than one species. See also B. zelleri. | Xerocomellus chrysenteron Michael Beug |
43b Spores truncate
................................................................................44
44a Cracks in cap reddish or pallid, cap dark olive to olive brown, (spores 4.5-7 um wide)
................................................................................Xerocomellus truncatus
(also known as Boletus truncatus )
CAP dark olive to olive-brown with red line under cuticle; 3-12 cm wide; dry suedelike, strongly areolate (cracked like mud) in age; flesh whitish then slowly yellowish, staining blue or blue-green when cut or bruised. TASTE and ODOR mild. TUBES and PORES yellow aging more olive; pores irregular 0.5-2mm - staining blue-green on exposure. STEM yellow above, red below; 4-8 cm long x 0.5-2.0 cm thick; naked to pruinose; base with dingy ochraceous mycelium. HABITAT on ground or sometimes decaying wood, under conifers and in mixed woods. DISTRIBUTION British Columbia, Washington, Oregon, Idaho, California. EDIBILITY unknown: MICROSTRUCTURES spores 10-15 x 4.5-6.5 um, many distinctly truncate; pileus cuticle a trichodermium having hyphae 8-14 um wide with brown incrustations, end cells tapered to an obtuse apex. REMARKS See also B. zelleri. | Xerocomellus truncatus Boleslaw Kuznik |
44b Cracks in cap pallid to yellow; cap gray brown to dingy yellowish brown, (spores 4-5 um wide)
................................................................................% Boletus porosporus var. americanus
(See Excluded Species.)
Gastroboletus is the name given to a group of fungi which look like aborted boletes. Often they are short and may even be covered by a peridial membrane. Their spores are formed in tubes which are so angled that spore discharge is impossible, or else outgrowth of tube walls or a peridial membrane blocks normal spore discharge. Propagation is probably accomplished through consumption and dispersal of spores by insects and animals. Like regular boletes, these semi-boletes are also mycorrhizal, usually with conifers. Most species are found at high elevations (usually over 5000 feet), giving rise to the theory that a short growing season, with the added handicap of dry conditions, often prevented normal growth of regular boletes in the distant past, causing development of these semi-bolete, semi-gastroid forms. Although only four species are currently on record for the Pacific Northwest, this key-maker thinks that PNW amateurs, who often hunt mushrooms in the mountains, could add to that list if they knew what to look for and recognized the fruitbodies, when found, as distinct species and not merely aborted boletes. Such finds should be taken to the regional or club bolete specialist, if possible. If not, field notes should be made on colors (plus changes on cutting or bruising, if any), tree association, elevation, etc.
1a Flesh not changing to blue when cut or bruised
................................................................................2
1b Flesh quickly changing to blue on exposure
................................................................................4
2a Surface yellow to red
................................................................................Gastroboletus vividus
"CAP" bolete-like in appearance but with cap margins strongly turned up when mature, yellow with red areas or blushed overall; 3-6 cm broad; flesh pale yellow, slowly staining pale red where exposed. TASTE and ODOR not distinctive. TUBES / GLEBA 10-20 mm long, adnate-seceding, aligned from slightly below horizontal to nearly vertically upward, often contorted, olive; pores 0.5-2 mm, circular to elliptic, brilliant yellow soon becoming olive and then red-orange to dark red, not turning blue where bruised. STIPE-COLUMELLA (STEM) brilliant to sordid yellow, red-furfuraceous (scurfy, covered with bran-like particles) at top; 2-3 cm long x 1-3 cm, abruptly bulbous below tube layer. HABITAT underground or partly emerging, with conifers above 1650m. (5400 ft.), July to September. DISTRIBUTION Oregon and California. EDIBILITY unknown. MICROSTRUCTURES spores 13-18 x 6-7 um; spindle-shaped or occasionally oval, smooth, inamyloid.
2b Surface grayish yellow with dark olivaceous fibrils, whitish, buff, or pale brown
................................................................................3
3a Surface whitish to buff or pale brown, no hanging veil remnants on cap margin, stem central to off-center, not rare
................................................................................Gastroboletus subalpinus
"CAP" covered by a whitish to buff membrane like the outside tissue of a puffball (which encloses the tubes / gleba also) - bolete-like in overall appearance, often pitted and irregular, usually covered by soil and debris; 6-10 cm broad; flesh 3-15 mm thick at disc, soft, usually white but occasionally with yellowish areas and rarely staining slowly pinkish to dull lilac when cut. TASTE mild, pleasant. ODOR mild to meal-like. TUBES / GLEBA 10-30 mm long, depressed to seceded from stipe-columella (stem), dingy yellow when young, aging olive brown; tubes sometimes oriented vertically near the stipe-columella but most curved and angled upwards at sides; pores small, circular to angular, concolorous with tubes, unchanging when bruised. STIPE-COLUMELLA (STEM) dirty white to buff, base sometimes orange yellow; dry but with the apex reticulate (covered with a network of raised fibrils) when the tubes have seceded enough to let it be seen; 2-5 cm long x 2-4.5 cm thick at apex, possibly enlarged in center or at base. HABITAT underground or partly emerging, with conifers in mountain and subalpine forests. DISTRIBUTION Washington, Oregon and California. EDIBILITY unknown. MICROSTRUCTURES spores 10-16 x 4.5-6 um; shape +/- variable, moderately thick-walled, with sterigmal appendages oblique, inamyloid.
3b Surface grayish yellow with dark olivaceous fibrils, giving a sordid gray appearance, hanging veil remnants on cap margin, stem laterally attached to cap, very rare
................................................................................Gastroboletus imbellus
"CAP" bolete-like in overall appearance, surface grayish yellow with dark olivaceous fibrils, giving a sordid gray appearance; 5 cm broad; hanging veil remnants on cap margin; flesh 20 mm thick, soft, white but with yellowish areas and with a rosy zone above tubes, not turning blue. TASTE slightly bitter. ODOR pungent-mealy. TUBES / GLEBA pores small, exposed but often blocked by folds and outgrowths of wall tissue; tubes not vertical, very short (up to 2mm long), pale grayish olive, unchanging. STIPE-COLUMELLA (STEM) dull yellowish in part, dingy cream in middle part, pale salmon with brown stains at base; upper half with minute blackish dots, often coalescing into patches 0.5mm across; 3.0 cm long x 1.5 cm thick at apex, equal but narrowing slightly at base. HABITAT developing underground, with conifers at 1650m. DISTRIBUTION Oregon, known from type collection. EDIBILITY unknown. MICROSTRUCTURES spores 7-10 x 2.5 um; elliptic or oboval, smooth, inamyloid. REMARKS atypical for Gastroboletus genus, and will probably be moved.
4a Distinct cap lacking, surface rose to brownish red or reddish brown, pore surface reddish orange to red, (spores 8-20 x 4-6 um)
................................................................................Gastroboletus ruber
(formerly Truncocolumella rubra Zeller)
"CAP" nearly spherical to top-shaped or lobed; rose to brownish red or reddish brown, peridium; 2-4 cm broad; dry, thin, smooth, usually disappearing over tube mouths; flesh pale yellow, staining blue instantly when exposed. TASTE not reported in the original description. ODOR not distinctive. TUBES / GLEBA tubes not vertically arranged, pores angular to irregular, up to 1 mm wide, surface irregular and uneven, tinged reddish orange to red, staining blue when bruised; spore mass pale yellow when young, becoming dark olive at maturity. STIPE / COLUMELLA (STEM) 1-2 cm long, 1-2 cm wide, tapered downward, colored like "cap", dry. HABITAT underground or emerging under hemlock with fir, spruce, and pine often present. DISTRIBUTION Cascade Mountains of Washington and Oregon, and reported from northern California. EDIBILITY unknown. MICROSTRUCTURES spores 8-20 x 4-6 um.
4b Cap distinct but typically stunted and irregularly shaped, surface yellowish brown to reddish brown or pale golden yellow, pore surface yellow to orange or red, (spores 11-18 x 7-9 um)
................................................................................Gastroboletus turbinatus
Many species of Leccinum are choice edibles. No species are yet known to be poisonous. Fortunately it is easy to learn to recognize the genus by the distinctive tufted scabers on the stem, which usually are white when young and darken to brownish or black by maturity. Many species of Leccinum have not yet been officially identified or described from the Pacific Northwest. Hence accurate notes need to be taken on the association of trees (or shrubs) and also on the color change, or series of color changes, which take place, after cutting, on the context at the junction of the stem and cap. After collection, a specimen should promptly be cut vertically through the cap and stem, and then observed frequently for 15-30 minutes to see whether color changes include reddish or lilac shades, or merely yellowish, brownish, grayish, or olive, and whether or not the changes progress to a dark bluish gray color which is almost black and often called "fuscous" in technical works. Perhaps a species will be named for you!
1a Cap predominantly whitish at first, sometimes tinged buff, pinkish, or tan; associated with birch
................................................................................2
1b Cap more strongly colored, or associated with other trees
................................................................................3
2a Cap whitish to grayish when young, darkening in age and often developing a greenish or olive tinge; growing in bogs, cedar swamps and wet birch woods; staining of flesh with FeSO4 slightly olive (var. holopus) or unrecorded (var. americanum)
................................................................................Leccinum holopus
CAP predominantly white or whitish when young, occasionally with gray, buff, tan, or pinkish tints, often darkening in age and developing a greenish tinge; 3-10 cm wide, bald or nearly so, often viscid when moist or in age, margin with a narrow sterile band of tissue; flesh white, unchanging when cut or rubbed. TASTE and ODOR not distinctive. PORES white to slightly grayish or pale dingy brown, unchanging or staining yellowish or brownish when cut or bruised. STEM whitish beneath the scabers that are whitish when young and darken to tan or darker in age, occasionally with green stains on lower part, 8-14 cm x 1-2 cm, equal or enlarging slightly downward. HABITAT on the ground in and around bogs, near swamps or wet birch woods. DISTRIBUTION of var. holopus eastern Canada south to New York, west to the northern Rocky Mountains (Bessette), of var. americanum eastern Canada south to New York, west to Minnesota; L. holopus reported from British Columbia (Schalkwijk-Barendsen), Washington (M. Seidl, pers. comm. var. americanum), Idaho (M. Beug, pers. comm.), Oregon ("what I believe to be L. holopus … with chestnuts and oaks that were probably brought in", Dick Bishop pers. comm.) EDIBILITY edible. MICROSTRUCTURES spores 14-20 x 5-6.5 um. Caulocystidia dark yellow brown in KOH for var. americanum. REMARKS var. americanum is nearly the same but has cap that is white at first, soon becoming dull vinaceous buff, and white flesh that changes to reddish when cut: its known range is eastern Canada south to New York and west to Minnesota and Schalkwijk-Barendsen designated her British Columbia record as var. americanum.
2b Cap white to tan or grayish tan, becoming pinkish buff to cinnamon-buff or darker; growing under birch, including dwarf birch in cold northern habitats or high mountain bogs; flesh stains instantly dark blue with application of FeSO4
................................................................................Leccinum rotundifoliae
(See also 21a.)
CAP whitish to tan to grayish tan, darkening in age; 2-8 cm wide; dry to slightly viscid, typically wrinkled and irregularly depressed; flesh white, unchanging or slightly pinkish when exposed. TASTE and ODOR not distinctive. PORES whitish when young, becoming dingy brown when old, unchanging when bruised. STEM whitish to pale tan beneath scabers that are whitish at first and brownish to grayish brown when old; 4-10 cm x 0.5-1.2 cm; flesh white, soon greenish blue in the base and brownish near the top. HABITAT under birch, July to September. DISTRIBUTION eastern Canada south to New York and west to Idaho and Alaska. EDIBILITY edible. MICROSTRUCTURES spores 16-23 x 5.5-8 um. Caulocystidia lemon-yellow in KOH.
3a Cap margin appendiculate from "flaps" of sterile tissue when young
................................................................................4
3b Cap margin naked when young
................................................................................20
4a Cut flesh not changing color much at junction of cap and stem
................................................................................5
4b Cut flesh changing to reddish or dull bluish-gray (or both)
................................................................................7
5a Cap dry and fibrillose to scaly, dull orange or yellow
................................................................................% L. subfulvum
(See Excluded Species.)
5b Cap viscid by maturity, rusty-iron red to liver-colored
................................................................................6
6a Cap surface granular-roughened like B. mirabilis, dark brown; stem base not bruising blue; under cedar, hemlock, and white pine
................................................................................Leccinum idahoense
6b Cap surface glabrous to appressed fibrillose, rusty-iron red; stem base exterior bruising blue easily; under pines
................................................................................Leccinum ponderosum
7a (4b) Cut flesh changing directly to dull purplish gray (= fuscous)
................................................................................8
7b Cut flesh changing first to reddish or winey shades, then fuscous
................................................................................12
8a Found under aspen
................................................................................9
8b Found under other kinds of trees
................................................................................11
9a Cap dull dark brown
................................................................................% Leccinum brunneum
CAP dull dark brown; 6-10 cm; dry, glabrous (bald) to suedelike young, aging +/- fibrillose; marginal flaps present; flesh changing to fuscous without reddish phase. TASTE and ODOR mild. TUBES and PORES white aging pale olive, bruising brown. STEM 8-15 cm long x 1.5-3 cm at apex, club-shaped; "scabers" white at first, darkening with age. HABITAT under aspen. DISTRIBUTION known from the higher elevations in the Sierra Nevada of California, but there are reports from Idaho (H. Thiers 1986, pers. comm. to L. Norvell; NAMA 1985 list). EDIBILITY unknown. MICROSTRUCTURES spores 15.5-19.5 x 4-6 um; cuticular hyphae lacking incrustations or pigment globules in Melzer’s reagent. | Leccinum brunneum Michael Wood (MykoWeb) |
9b Cap orange-red, dark red, or liver-colored
................................................................................10
10a Cap orange-red to dull orange; pores white when young
................................................................................Leccinum insigne
10b Cap very dull reddish brown; pores cinnamon when young
................................................................................% Leccinum subtestaceum
CAP very dull reddish brown; 4-12 cm, +/- glabrous (bald), marginal flaps when young; flesh white, winey-gray when cut but lacking distinct red phase. TASTE and ODOR not distinctive. TUBES and PORES cinnamon-brown when young, becoming paler in age, tubes slowly staining vinaceous gray when cut. STEM scabers soon blackish, stem flesh sometimes stained bluish near base; 7-12 cm x 2-3 cm. HABITAT under aspen (and birch according to Bessette). DISTRIBUTION Massachusetts to the Great Lakes Region (Bessette et al.; Both). Kit Scates comment in the 1982 key is "Authoritative confirmation of this species in the Pacific Northwest is desirable." EDIBILITY edible. MICROSTRUCTURES spores 11-15 x 4-5.5 um; some cuticular hyphae showing pigment globules in Melzer’s.
11a (8b) Only under spruce and fir, usually at high elevations; pallid; dry to somewhat viscid
................................................................................Leccinum clavatum
11b Only under manzanita and madrone near coast; dark red; viscid
................................................................................Leccinum manzanitae
12a (7b) Stipe with dense coal black scabers at all stages, under birch or sometimes other hardwoods
................................................................................13
12b Scabers less prominent, or lighter in color especially when young, (or if blackish then cap is dull tan to snuff-brown and growth is under aspen)
................................................................................14
13a Cap at first dull orange to pinkish tan or brownish; cap scaly in age; flesh stains blue gray with application of FeSO4; (caulocystidia frequently fusoid-ventricose with elongated necks)
................................................................................Leccinum atrostipitatum
13b Cap at first bright brick-orange, fading to dull orange to pinkish tan; cap less scaly in age; flesh stains bright green with application of FeSO4, (caulocystidia clavate, clavate-mucronate or sometimes fusoid-ventricose)
................................................................................Leccinum testaceoscabrum
(According to Breitenbach & Kränzlin (1991) the correct name is Leccinum versipelle (Snell) Fr.)
14a (12b) Cap white, often with a pink tint, when fruiting body develops in moist weather, light brown to patchy white and brown when it develops in dry weather
................................................................................% undescribed Leccinum
CAP white (often with a pink tint) when fruiting body develops in moist conditions, pale brown or with patches of white and pale brown when it develops in dry conditions, 7-15cm; surface dry, often uneven, sparsely appressed-fibrillose, fibrils more numerous in darker-colored areas, portions of surface finely and superficially areolate in dry conditions, sterile margin 2-5mm, the tissue usually broken into segments especially when young; flesh up to 3.5cm thick, white changing to purplish pink then dark gray with a purple or violet tint at stipe apex and other random areas. TASTE and ODOR mild. PORES white changing to brown in age, bruising dark brown slowly, more than 1 pore per mm. STEM ground color and scabers white (often with pink tint), remaining so in moist weather, darkening in zones near mid-stipe to reddish orange or brown in dry weather; sometimes developing reddish or purplish stains near base after handling, 7-15 cm x 2.3-3.7 cm at apex, 3-6 cm at base, equal or enlarging evenly downward, quickly tapering to a dull point; flesh white, color changes similar to cap flesh, sometimes slowly pinkish purple in base. HABIT solitary to scattered. HABITAT soil or duff in Western Hemlock forest with occasional Douglas-fir. DISTRIBUTION known from only one site near SE side of Mt. Hood in Oregon. EDIBILITY apparently edible (several people have eaten it with no ill effects). MICROSTRUCTURES spores 11.5-18(20) x (3.5)4-5 um, fusiform or subfusiform (somewhat spindle-shaped). REMARKS description by Richard Bishop
14b Cap orange, dull cinnamon, reddish brown, or dark red (when in doubt use this option)
................................................................................15
15a Cap glabrous (bald), dull orange to dull cinnamon
................................................................................16
15b Cap fibrillose to scaly while mature (may be bald when old); darker or brighter or lighter than dull orange to dull cinnamon
................................................................................17
16a Pores exuding a watery latex (juice) when cut
................................................................................% L. truebloodii
(See Excluded Species.)
16b Pores not exuding a clear latex when cut
................................................................................Leccinum discolor
17a (15b) Cap dark orange to dark red
................................................................................18
17b Cap paler than orange or darker than red
................................................................................19
18a Stem conspicuously club-shaped and thick at base when young
................................................................................% Leccinum fallax
18b Stem not conspicuously thick at base when young
................................................................................Leccinum aurantiacum
CAP orange to apricot to brick red; 5-15 cm wide; dry, aging +/- viscid; marginal flaps present; flesh changing to wine color before fuscous. TASTE and ODOR not distinctive. TUBES and PORES pallid when young, bruising olive or brown or unchanging. STEM 10-16 cm x 1-3 cm, equal or enlarging downward but not conspicuously clavate-bulbous; scabers whitish to buff, darkening to orange-brown to reddish brown and finally blackish brown, at least over lower part, occasionally with blue-green or yellowish stains on lower part. HABITAT under aspen or pine. DISTRIBUTION Washington and California, and reported from Oregon, Idaho, and Montana, fairly common in Pacific Northwest. EDIBILITY edible and considered choice by many people. MICROSCOPIC spores 13-16 x 3-4.5 um; cuticular hyphae with abundant pigment globules in Melzer’s reagent. REMARKS L. discolor is similar but has duller cap color and lacks orange brown pigment granules in hyphae in Melzer's reagent.
19a (17b) Cap pale pinkish cinnamon to vinaceous; under Whitebark Pine
................................................................................% L. incarnatum
(See Excluded Species.)
19b Cap liver-brown; fibrillose-scaly; under mixed conifers
................................................................................Leccinum fibrillosum
20a (3b) Cut flesh not changing to reddish or purplish-gray(= fuscous)
................................................................................21
20b Cut flesh changing to a reddish or fuscous color
................................................................................22
21a Cap whitish to pallid becoming pale tan on disc, darkening in age; under dwarf birch in cold northern habitats or high mountain bogs
................................................................................L. rotundifoliae
(See 2b for description.)
21b Cap gray-brown to dull tan; usually under birch
................................................................................Leccinum scabrum
22a (20b) Cap dark brown, flesh changing quickly to coral on cutting
................................................................................% Leccinum roseofractum
CAP dark brown; up to 11.5 cm; greasy then dry and +/- scaly; no marginal flaps; flesh turning immediately coral, and later faintly lilac-gray. TASTE and ODOR mild. TUBES and PORES white aging drab (dingy gray-brown). STEM robust, 8 cm long x 2.5 cm at apex and 4 cm at base; scabers light at top and fused into dense black network on lower half. HABITAT with birch. DISTRIBUTION New York, Pennsylvania, and Ohio, included in the key by Kit Scates, further distribution records are desirable. EDIBILITY probably edible. MICROSTRUCTURES spores 14.3-16.4 x 5.0-5.7 um.
22b Cap pale buff, flesh slowly and erratically turning winey-pink
................................................................................% L. cretaceum (?)
(See Excluded Species.)
The species in this key are contained in the genera Suillus and Fuscoboletinus of Smith and Thiers, which include the genus Boletinus of some other authors.
1a Stem with persistent ring or ring-zone
................................................................................2
1b Stem without persistent ring or ring-zone
................................................................................15
2a Stem flesh staining bluish-green in 15-30 minutes; pores staining brown; mostly under Douglas-fir; one species under larch
................................................................................3
2b Stem flesh not staining bluish-green, etc.
................................................................................7
3a Tubes and pores whitish to grayish and not becoming truly yellow
................................................................................Suillus viscidus
(also known as Fuscoboletinus aeruginascens (Secretan) Pomerleau & A.H. Sm., Fuscoboletinus viscidus (Linne) Grund & Harrison, and Suillus laricinus (Berkeley) Kuntze)
(See also 9a.)
3b Tubes and pores yellowish when young to greenish olive in age
................................................................................4
4a Cap fibrillose-scaly, especially young, brick-red to cinnamon; spore print dull cinnamon; no rosy layer beneath
................................................................................Suillus lakei
4b Cap not both fibrillose-scaly and so colored
................................................................................5
5a Ring gelatinous, heavy, orange
................................................................................Suillus ponderosus
5b Ring fibrillose, +/- whitish
................................................................................6
6a Cap with streaks or scattered flat fibrils; buff-colored; tubes compound; under Douglas-fir
................................................................................Suillus caerulescens
6b Cap bald, orange-cinnamon to cinnamon; under spruce and true firs
................................................................................Suillus imitatus
7a (2b) Cap dry, woolly-fibrillose-scaly; under larch
................................................................................8
7b Cap viscid (slimy), not woolly-fibrillose-scaly; under various trees
................................................................................9
8a Cap brown or yellow; stem hollow at base
................................................................................Suillus cavipes
8b Cap rosy-red; stem not hollow
................................................................................Suillus ochraceoroseus
(also known as Fuscoboletinus ochraceoroseus)
9a (7b) Pores and tubes gray-brown; cap olive, tan or gray, viscid (slimy); under larch
................................................................................Suillus viscidus
(See description under 3a.)
9b Not as described above
................................................................................10
10a Ring gelatinous, colored +/- like cap
................................................................................11
10b Ring +/- fibrillose, whitish
................................................................................13
11a Outer surface of ring purplish in wet weather or when old
................................................................................Suillus luteus
11b Outer surface of ring not purplish in wet weather or when old
................................................................................12
12a Cap bay red with yellow edge (occasionally all yellow); under larch
................................................................................Suillus grevillei
12b Cap, stem and ring olivaceous when young, aging cinnamon; under conifers
................................................................................Suillus subolivaceus
13a (10b) Cap mustardy yellow with flat brown scales near edge
................................................................................Suillus sibiricus
(See also 18a.)
CAP 3-10 cm, ground color chamois to dingy olive-yellow or brighter yellow, with brownish appressed scales overall and patches of veil tissue hanging from margin; viscid to glutinous; flesh pale olive yellow, slowly dull cinnamon when cut. TASTE +/- acid. ODOR not distinctive. TUBES and PORES 1-1.5 cm deep, dingy ochraceous; adnate becoming decurrent; pores 1-2 mm broad, angular and often compound ("tubes within tubes"), staining dull cinnamon when bruised, not blue. STEM 5-10 cm x 0.7-1.5 cm, yellow when young, dingy ochraceous, often stained vinaceous near base; glandular-dotted overall; sometimes with annulus. HABITAT under White Pine, fall. DISTRIBUTION very common in N. Idaho, but also Washington, Oregon, Montana, and found on foray lists from British Columbia. EDIBILITY not recommended. MICROSTRUCTURES spores 8-11 x 3.5-4.2 um. REMARKS often mistaken for S. americanus (see Excluded species, but probably actually a synonym of S. americanus (see Nguyen et al.) Suillus americanus is said to have a brighter yellow cap with reddish to cinnamon patches and a thinner stem that is typically less than 1 cm thick, and it does not form an annulus. S. flavidus has a smaller somewhat more umbonate cap that has fewer scales and lighter color, and has a well developed gelatinous annulus. | Suillus sibiricus Andrew Parker |
13b Cap not mustardy yellow or not with flat brown scales near edge
................................................................................14
14a Cap olive, umbonate when young
................................................................................Suillus flavidus
(description here from 1982 key as S. umbonatus Dick & Snell, synonymized by Moser 1997 with S. flavidus (Fr.) Singer)
14b Cap streaked dull yellow-brown, ring fragmentary; under 2- and 3-needle pines
................................................................................Suillus pseudobrevipes
15a (1b) Cap margin with fringe or cottony roll when young
................................................................................16
15b Cap margin naked when young (cap surface may be fibrillose to scaly or not)
................................................................................23
16a Stem with a granular rash or dark brownish spots
................................................................................17
16b Stem lacking such a granular rash
................................................................................22
17a Cap with flat brownish scales near edges, cap mustardy yellow to brighter yellow
................................................................................18
17b Cap without flat brown scales
................................................................................19
18a Stem 0.6-1.5cm thick at maturity, cap mustardy yellow to ocher-yellow
................................................................................S. sibiricus
(See 13a for description.)
18b Stem typically less than 1cm thick at maturity, cap bright yellow to ocher-yellow
................................................................................S. americanus
(See Excluded species.)
19a Partial veil like a membrane (skin)
................................................................................20
19b Partial veil cottony or woolly
................................................................................21
20a Cap dark brown in all ages; fringe like dark skin; stem whitish
................................................................................* Suillus borealis
20b Cap white, bruising brown; with brown slime; under Sugar Pine or Lodgepole Pine
................................................................................Suillus brunnescens
21a (19b) Granular spots on stem conspicuous at all ages; cap yellowish young, red-orange-brown when old; under Beach Pine and Bishop Pine
................................................................................Suillus glandulosipes
21b Granular spots obscure when young; cap pale pinkish-cinnamon or pale ochraceous; under Lodgepole Pine
................................................................................Suillus neoalbidipes
(formerly known as S. albidipes (Peck) Singer)
CAP 4-10 cm; gelatinous; pallid, becoming pale ochraceous or vinaceous-cinnamon; with a zone of soft cottony whitish to vinaceous-buff material along the margin when young, perhaps patchy in age; flesh white, slowly becoming yellow, not turning blue. TASTE and ODOR not distinctive. TUBES and PORES about 5 mm deep, pale dingy yellow; pores round, minute (+/- 3 per mm), usually not staining when bruised. STEM 3-6 cm x 1.0-1.5 cm, white, becoming yellowish in upper part, brownish near base, glandular dots best visible in age. HABITAT under 2- and 5-needle pines, late summer and fall. DISTRIBUTION Oregon collection at Oregon State University Herbarium, reported from British Columbia. EDIBILITY edible. MICROSTRUCTURES spores 6-10 x 2-3 um. REMARKS the colors of these two species are variously described, and knowledge of both species would be required to distinguish them by color. Since Beach Pine and Lodgepole pine are the same species, this distinction may be unreliable as well.
22a (16b) Veil cottony; pores small and round, not staining brown; tube length normal; cap dull yellowish
................................................................................Suillus albivelatus
22b Veil membranous; pores angular but not large; tubes unequal so pore surface is irregular
................................................................................% S. appendiculatus
(See Excluded Species.)
23a (15b) Stem with granular rash of dark brownish spots
................................................................................24
23b Stem without such a rash
................................................................................32
24a Flesh bluing when cut, cap more or less woolly
................................................................................25
24b Flesh not bluing when cut; cap glabrous (bald) to fibrillose-scaly
................................................................................27
25a Cap yellow-orange; pores brownish when young; under pines or other conifers
................................................................................Suillus tomentosus
25b Cap another color
................................................................................26
26a Cap olive to brown
................................................................................Suillus tomentosus var. discolor
A variant differing mainly in having much duller colors. The buttons are covered with dense grayish fibrils; mature specimens appear olive-brown to olive-gray. By contrast, the pores of young buttons are not so brown as in the type variety. It is fairly common in Idaho, according to Bessette et al.
26b Cap red
................................................................................% S. ruber
(See Excluded Species.)
27a (24b) Cap conspicuously fibrillose-scaly when young, olive-brown to vinaceous brown at first, becoming paler, revealing cinnamon to ochraceous ground color, recorded Oregon and California
................................................................................Suillus fuscotomentosus
(A synonym is Suillus acerbus A.H. Sm. & Thiers.)
CAP when young densely coated with olive-brown to dark brown or vinaceous brown fibrils; when mature, with a thinner and more widely separated layer of brown fibrils on buff to yellow or pale ocher ground color; moist and slightly viscid or dry, conspicuously fibrillose to fibrillose-scaly, but sometimes nearly bald when old; flesh pale yellow to yellow, not staining when exposed. TASTE not distinctive or weakly acidic and unpleasant. ODOR not distinctive. PORES pale yellow at first, becoming yellow to olive-yellow or dull golden yellow when mature, not staining where bruised, pores angular, 1-2 per mm. STEM 4-10 cm x 1-3 cm, nearly equal or enlarged downward; yellow to pale yellow, with dense conspicuous brown to vinaceous brown glandular dots; dry. HABITAT under pine. DISTRIBUTION Oregon and California, fairly common according to Bessette et al. EDIBILITY edible. MICROSTRUCTURES spores 9-12 x 3-4 um. | Suillus fuscotomentosus Fred Stevens (MykoWeb) |
27b Cap glabrous (bald)
................................................................................28
28a Pores small (up to 1 mm); cap pallid at first, then some shade of tan, brown, cinnamon brown, yellow-brown or orange-brown; cap over 4cm when mature
................................................................................Suillus granulatus
28b Pores large (over 1 mm), or cap differently colored, or cap small (less than 4cm) even when mature
................................................................................29
29a Cap dark red-brown to pinkish cinnamon; stem usually narrowed at base; tubes decurrent, pores radially arranged and elongated
................................................................................Suillus punctatipes
29b Not combining features above
................................................................................30
30a Cap whitish when young, becoming yellowish in age; stem with pinkish brown dots that darken with age; associated with white pine
................................................................................Suillus placidus
CAP 3-9 cm, viscid, glabrous (bald); white or whitish when young, yellowish in age; flesh white to pale yellow, slowly staining pale vinaceous when exposed, not turning blue. TASTE and ODOR not distinctive. PORES white soon becoming yellowish and in age ocher-yellow, unchanging when bruised, often with pinkish droplets when moist, pores angular to irregular, 0.5-2 mm wide. STEM 4-9 cm x 0.6-1.2 cm, white, becoming yellow when old, with conspicuous pinkish brown dots and smears that become reddish brown or darker when old. HABITAT under White Pine. DISTRIBUTION reported from Washington by Isaacs & Stuntz. EDIBILITY edible. MICROSTRUCTURES spores 7-9 x 2.5-3.2 um. REMARKS S. pallidiceps is similar but lacks conspicuous glandular dots, is associated with Lodgepole Pine, and is known only from Idaho.
30b Not combining features above
................................................................................31
31a Cap convex to plane, pale yellow beneath smoky slime, becoming paler in age; stem stout; tubes depressed at stem
................................................................................% Suillus flavogranulatus
31b Cap umbonate or bell-shaped, streaked brown & yellow; stem slender; in clumps of 40-50; under Beach Pine
................................................................................% Suillus helenae
CAP 1.5-4 cm, slimy viscid; dingy yellow streaked brown; almost conic to bellshaped to umbonate; flesh unchanging, ochraceous. TASTE and ODOR not distinctive. TUBES and PORES yellow; tubes compound ("having tubes within tubes"); pores angular and radially arranged. STEM 3-6 cm x 0.4 cm (rather slender), yellowish, lacking a ring but heavily covered with concolorous resinous glandular dots, darkening slowly; base ending in copious white rhizomorphs. HABIT grows in dense clusters. HABITAT under Beach Pine. DISTRIBUTION at least Idaho and Oregon. EDIBILITY unknown. MICROSTRUCTURES spores 6-10 x 3-4 um.
32a (23b) Cap when young white, aging pale yellow and finally dull cinnamon-buff; under Lodgepole Pine
................................................................................% Suillus pallidiceps
32b Cap darker than above
................................................................................33
33a Under 2- and 3-needle pines; cap when young brown but aging yellowish; stem often short
................................................................................Suillus brevipes
33b Under oaks and other hardwoods; cap red-brown, slimy
................................................................................Boletus flaviporus
(See Key to Species of Boletus etc.)
CAP 1-10 cm, dry and powdery at first, becoming appressed-fibrillose to fibrillose-scaly; bright sulfur-yellow, becoming orange-red to brownish red from center; typically with hanging yellow veil remnants; flesh white to pale yellow, slowly staining pale blue then dingy yellow to pale brown when cut. TASTE and ODOR not distinctive. TUBES and PORES tubes 5-8 mm deep, bright yellow, becoming dingier or grayish brown at maturity; pores small (1-3 per mm), turning blue then brown when bruised. STEM 4-15 cm x 0.6-1.6 cm, bright sulfur-yellow and powdery, at least in lower part, sometimes leaving a yellow annulus. HABITAT on ground in woods. DISTRIBUTION includes California, also recorded from Oregon (Coos Co.); rare. EDIBILITY edible. MICROSTRUCTURES spores 8-10.5 x 4-5 um, elliptic to oval, smooth. REMARKS spore deposit is olive-gray to olive-brown.
Boletus fragrans Vittad.
CAP brown to olive brown on the disc, paler on the margin; 6-15 cm wide; irregular and uneven; dry and suedelike, aging +/- glabrous (bald); flesh cream color to yellow, bluing on injury. TASTE and ODOR mild, odor pleasant in Europe. TUBES and PORES all yellow when young, aging dark yellow, bluing when bruised. STEM yellow at apex (occasionally with reddish band), more tan toward base, 4-10 cm long x 1-3.5 cm thick, +/- equal; not reticulate, glabrous to granular. HABITAT in U.S. known only from high elevations under conifers, usually Red Fir. DISTRIBUTION reported by Slipp and Snell from Idaho, but Singer thought their species different from the European one; Thiers says that in California it has only been found in the Yuba Pass and Luther Pass areas; not included by Bessette et al. for North America. EDIBILITY edible in Europe, unknown for U.S. collections. MICROSTRUCTURES spores 13-17.5 x 5-7.8 um; pileus cuticle a trichodermium of hyphae with spiral encrustations.
Boletus porosporus (Imler) Watling var. americanus A.H. Sm. & Thiers
CAP gray-brown to dingy yellowish brown; 4-6.5 cm wide; densely tomentose (plush-like), dry; flesh pallid yellowish white, unchanging when cut. TASTE and ODOR mild. TUBES and PORES tubes yellow, pores yellowish gray, staining blue on exposure; pores round, 1-2 per mm. STEM upper area roughened like a finely ornamented Leccinum, ornamentation dull brown on a reddish to brown ground color, yellowish mycelium over base, 5-6 cm long x 0.8-1.2 cm thick at top. HABITAT not specified. DISTRIBUTION described from Idaho (without a Latin diagnosis), but E. Both quotes Smith (1975), "it occurs throughout the western United States but is especially common early in the fall season in the rain forests of the coast". EDIBILITY unknown. MICROSTRUCTURES spores 13-16 x 4-5 um, amyloid at first but quickly changing, apex truncate or notched; cap cuticle a trichodermium of enlarged cells often encrusted with cinnamon brown material. REMARKS As Ernest Both indicates, there is considerable nomenclatural controversy about this taxon. There is also var. porosporus, also known as Xerocomus porosporus Imler var. porosporus, said to occur in Washington, and to have wider spores and less areolate cap: a taxon that has been treated by Grund and Harrison (1976) as a synonym of Boletus truncatus (Singer, Snell, & Dick) Pouzar. Boletus porosporus is not included by Bessette et al. for North America.
CAP pale buff-pink to pale tan; very convex; approximately 5 cm diameter; dry and dull, becoming areolate in dry weather; flesh on cutting reddish before fuscous; TASTE and ODOR not distinctive. TUBES and PORES white when young, aging tan; deeply depressed near stem. STEM clavate-bulbous when young, aging almost equal; ground color very pale, ornamentation very variable, upper half almost smooth to fibrillose-roughened, lower half with not-very-dense blackening scabers. HABIT and HABITAT gregarious to cespitose under birch and Trembling Aspen. DISTRIBUTION "Material described is that found in northern Idaho; it may or not be conspecific with L. cretaceum of Europe" (this comment and the query after the name are both in the original key by Kit Scates). Neither Bessette et al. nor E. Both list the species for North America. EDIBILITY edible. MICROSTRUCTURES spores 14.3-16.4 x 5.0-5.7 um.
Leccinum incarnatum A.H. Sm., Thiers & Watling
CAP pale pinkish cinnamon to vinaceous; 5-15 cm; dry, matted fibrillose, cracking in age; margin flaps present when young; flesh when cut slowly vinaceous buff then vinaceous gray. TUBES and PORES small, gray-brown when young, bruising dingy tan. STEM white with vinaceous-buff scabers that become brown but not black; 4-8 cm x 2-2.5 cm at apex, 4 cm thick at base. HABITAT under Whitebark Pine (Pinus albicaulis). DISTRIBUTION described from Idaho, but not included by Bessette et al. for North America. EDIBILITY probably edible. MICROSTRUCTURES spores 13-16 x 3-4.5 um; cuticular hyphae not having pigment globules in Melzer’s reagent.
Leccinum subfulvum A.H. Sm., Thiers & Watling
CAP dull orange or yellow; 6-12 cm, convex, dry and fibrillose to scaly, marginal flaps; flesh white, not changing. TUBES and PORES not staining. STEM 5-10 cm long and 1-2 cm wide at top, club-shaped but pointed at base; ornamentation colored as cap. HABITAT under Lodgepole Pine, fall. DISTRIBUTION rare, described from Washington; not included by Bessette et al. for North America. EDIBILITY probably edible. MICROSTRUCTURES spores 13-17 x 4.5-5.5 um.
Leccinum truebloodii A.H. Sm., Thiers & Watling
CAP orange to dull tan to snuff-brown, becoming blackish when bruised; 4-9 cm; glabrous (bald) at first but cracking in age; marginal flaps present; flesh cream, becoming pinkish on cutting before changing further. TASTE mild and slightly nutty. TUBES and PORES creamy to chamois or grayish tan, bruising blackish, exuding a clear fluid when cut. STEM 6-8 cm x 3-3.5 cm; flexuous (curved both ways); covered entirely with blackish fibrillose squamules (fine scales). HABITAT under aspen, collected in Owyhee County by Ted Trueblood. DISTRIBUTION described from Idaho, but not included by Bessette et al. for North America. EDIBILITY edible. MICROSTRUCTURES spores 14-18 x 5-7.5 um; pigment globules not present in cuticular hyphae in Melzer’s reagent.
Suillus americanus (Peck) Snell ex Slipp & Snell
CAP 3-10 cm, ground color bright yellow to ocher-yellow, with brownish scales or patches especially toward margin, patches of veil tissue hanging from margin; viscid to glutinous; flesh yellow, staining vinaceous brown when cut but not in stem base. TASTE not distinctive or +/- acid. ODOR not distinctive. TUBES and PORES 0.6-1 cm deep, yellow becoming browner, staining vinaceous brown when bruised, not blue; adnate to decurrent; pores 1-2 mm broad, angular. STEM 3-9 cm x 0.3-1.0 cm, hollow when old, often crooked; yellow, with vinaceous brown stains where handled or when old; glandular-dotted overall; without annulus. HABITAT under White Pine, fall. DISTRIBUTION the presence of this species in the Pacific Northwest is debatable. There are vouchers at University of Washington (D. Stuntz 1976, D. Stuntz 1976, both from King County), and Oregon State University (including A.H. Smith 1946), but many old records are really S. sibiricus (which was described in 1938 as Ixocomus sibiricus by R. Singer). H. Thiers wrote in 1975, "it is now believed that S. americanus does not occur west of the Rocky Mountains and that many reports of its presence in the west have been based on basidiocarps of S. sibiricus". There remains also the possibility that they are really the same species, but that possibility needs to be explored further at the molecular level. EDIBILITY yes. MICROSTRUCTURES spores 8-11 x 3-4 um. REMARKS S. sibiricus may form an annulus. According to Thiers, perhaps the most obvious difference from S. sibiricus is the tendency of stem flesh of the base to stain vinaceous in S. sibiricus. S. flavidus has a smaller somewhat more umbonate cap that has fewer scales and lighter color, and has a well developed gelatinous annulus.
Suillus appendiculatus (Peck) A.H. Sm. & Thiers
This is Suillus appendiculatus (Peck) A.H. Sm. & Thiers, or Boletinus appendiculatus Peck, (not Suillus appendiculatus (Schaeffer: Fr.) Kuntze which is the same as Boletus appendiculatus (Schaeffer: Fr.) Secretan.
CAP 10-20 cm (comparatively large); glabrous and possibly viscid; dingy yellow; flesh pale yellow, unchangeable. TUBES and PORES yellow; pores medium but angular and unequal, staining brown when injured. STEM 5-7.5 cm x 0.8-1.5 cm; slightly thickened at base, neither annulate nor glandular dotted. HABITAT under or near fir trees, late fall or winter. DISTRIBUTION collected by Yeomans in Washington state according to Smith & Thiers, but not included by Bessette for North America. MICROSTRUCTURES spore size 7.5-9.5 x 3-3.5. REMARKS not well known.
Suillus ruber Singer & Sipe
CAP bright red sprinkled with darker spots, viscid, fibrillose; flesh yellow turning blue on exposure. TUBES and PORES greenish yellow when mature, pores small. STEM yellow, ornamented with glandular dots but no veil. HABITAT under conifers. DISTRIBUTION described from Oregon, but not included by Bessette et al. for North America. EDIBILITY unknown. MICROSTRUCTURES spores 7.8-9 x 2.3-4 um; cuticle an ixotrichodermium. REMARKS It has been suggested that this may be merely old brightly colored S. tomentosus which often ages red. Anybody finding a Suillus, red when young, that turns blue, should get it to a bolete specialist.
abruptly bulbous - of stem base, having a bulb or bulging area that flares at roughly right angles to stem
acidulous - slightly acid
adnate - referring to pore surface, attached squarely to stem without a notch
adnate-seceding - adnate at first, then becoming free of stem
amyloid - staining bluish to gray to black in Melzer's reagent
angular - with corners or angles, as opposed to round
annulus - ring or collar of tissue on stem formed by rupture of the veil that initially joins the stem to the cap edge
appendiculate - margin of cap fringed with hanging fragments of the veil
appressed - flattened down
areolate - surface cracked into plaques or blocks, like the cracking that occurs when mud dries in the sun
asperulate - appearing roughened with tiny points or warts
bulb - a part shaped like the underground part of an onion or daffodil or similar plant
bulbous - having a bulb or bulging area; of stem, with an enlarged base
button - young fruiting body before it has opened up
caulocystidia - cystidia on stem
cespitose - growing in tufts or close clusters from a common base, but not grown together
clavate - of stem, implies base is thicker and stem tapers upward, same as club-shaped; when used of cystidia or basidia, implies part that extends outward beyond the hymenium is thicker
columella - a sterile column of tissue projecting into the spore mass of Gastroboletus and other genera
context - flesh of cap or stem (excluding the surface layer)
cortex - a more or less thick outer covering
cuticle - the cap skin or surface layer of cells
cutis - type of "cuticle" (pellis), surface layer of cap cells if they are differentiated from the underlying tissue and arranged more or less parallel to cap surface
decurrent - refers to pores that run down the stem, the attachment of the tubes at stem is wider than average thickness of the tube layer
depressed - of cap, having middle lower than the edge; of pore layer, sunken below level of attachment to stem
dextrinoid - staining yellowish brown or reddish brown in Melzer's reagent
drab - brownish gray or grayish brown, sometimes with yellowish or violet overtones
equal - of a stem, the same diameter throughout its length, cylindric
fibrillose - composed of delicate fibers which are long and evenly arranged on the surface
fibril - delicate fiber
flexuous - of the stem, or of cystidia, curved alternately in opposite directions
floccose - with easily removed cottony or woolly tufts, having the appearance of cotton flannel, with a soft cottony texture
fuscous - color of a very dark storm cloud: variously described as combinations of gray, brown, purple, or black
fusiform - spindle-shaped, fairly slender and narrowing from middle to both ends
fusoid - somewhat spindle-shaped, almost spindle-shaped or fusiform
gelatinous - jelly-like in consistency or appearance; applied to tissue whose hyphae become partially dissolved and glutinous in wet weather and when mounted in water under the microscope appear more transparent and wider, loosening from one another
glabrous - bald, without hairs or raised fibers or scales or raised patches
glandular - with sticky drops or glands
gleba - the spore mass of Gastroboletus and other genera
gluten - slime, the dissolved gelatinous hyphae of certain tissues
glutinous - slimy, having a highly viscid gelatinous layer, more than viscid
gregarious - growing in close groups but not tufted or clustered
inamyloid - remaining clear or becoming yellow in Melzer's reagent, not amyloid or dextrinoid, same as nonamyloid
laticiferous - bearing latex (juice)
membranous - like a membrane or skinlike or somewhat like kleenex
mucronate - pointed, tipped with an abrupt, short point from a flatter surface
pallid - very pale in color, almost a dull whitish
pellicle - same as cuticle or as thinner and more definite
peridium - the outer covering enclosing a spore mass
pileipellis - the outer cellular layer of the cap (pileus), excluding veils, used in microscopic descriptions, also know as cap cuticle
pileus - cap of a mushroom
plane - having a flat surface
pruinose - looking finely powdered or finely granular
reticulate - covered with a network of interlacing lines, ridges, or folds
scaber - small stiff projection on stem surface, especially in Leccinum
squamule - fine scales
squamulose - with small scales
sterile - not producing spores
stuffed - containing loose material in the interior, not hollow or solid
sub- near, nearly, more or less, somewhat, slightly; below or under
tomentose - covered with soft hairs, often soft densely matted hairs, like a woollen blanket
tomentum - a covering of densely matted woolly hairs
trama - the tissue under the surface cell layers of cap or stem, or between the tube wall layers of boletes, usually referring to the flesh (context) as seen through the microscope
trichodermium (trichoderm) - a cuticle with hyphae projecting from the surface more or less perpendicularly as viewed under microscope
viscid - sticky but not slimy or lubricous: the mushroom usually feels somewhat slimy or slippery when wet but when dry may need to be wetted slightly to feel sticky
GENUS AND SPECIES | KEY ENTRIES |
AUREOBOLETUS Pouzar | |
A. flaviporus (Earle) Klofac | B8a, B36a |
A. mirabilis (Murrill) Halling - see Boletus mirabilis | |
BOLETUS Fr. | |
B. abieticola Thiers - see Butyriboletus abieticola | |
B. aereus Bull. - see Boletus regineus | |
B. amygdalinus (Thiers) Thiers - see Suillellus amygdalinus | |
Boletus amylosporus (A.H. Sm.) Wolfe | B35b |
= Porphyrellus amylosporus A.H. Sm. | |
= Tylopilus amylosporus (A.H. Sm.) A.H. Sm. | |
B. appendiculatus (Schaeff.) Secr. -misapplied to Butyriboletus persolidus | |
B. barrowsii Thiers and A.H. Sm. | B13a, B14b |
B. calopus Fr. - see Caloboletus calopus | |
B. chrysenteron (Bull.) Fr. - See Xerocomellus chrysenteron | |
B. coccyginus Thiers | B39a |
B. coniferarum Dick and Snell - see Caloboletus conifericola | |
B. eastwoodiae (Murrill) Sacc. & Trotter - see Rubroboletus eastwoodiae | |
Also incorrectly for B. pulcherrimus. | |
B. edulis Bull. | B11b, B13a, B14a, B14b |
B. erythropus - see B. luridiformis | |
B. fibrillosus Thiers | B14b, B20a |
B. flaviporus Earle - see Aureoboletus flaviporus | |
B. fragrans Vittad. | B30a, Excluded Species |
B. haematinus Halling - see Rubroboletus haematinus | |
B. hemichrysus Berk. & Curtis | B26b |
B. luridiformis Rostk. | B24a |
= B. erythropus (Fr.) Krombh. | |
B. mirabilis (Murrill) Murrill | B5a, B26a |
= Boletellus mirabilis (Murrill) Singer | |
= Aureoboletus mirabilis (Murrill) Singer | |
B. mottiae Thiers | B11b, B14b |
B. oregonensis | B7, B8 |
B. pinicola - see B. rex-veris | |
B. pinophilus - see B. rex-veris | |
B. piperatoides - see Chalciporus piperatoides | |
B. piperatus Bull. - see Chalciporus piperatus | |
B. porosporus (Imler) Watling var. americanus A.H. Sm. & Thiers | B44b, Excluded Species |
B. pulcherrimus Thiers and Halling - see Rubroboletus pulcherrimus | |
B. pulverulentus Opat. | B28b |
B. puniceus - see B. amygdalinus | |
B. radicans Pers. sensu Kallenbach - see Caloboletus radicans | |
B. rainisii A.E. Bessette and O.K.Miller | B28a |
B. regineus D. Arora and Simonini | B11a, B14b |
B. regius Krombholz - see Butyriboletus autumniregius, | |
Butyriboletus primiregius, and Butyriboletus querciregius | |
B. rex-veris D. Arora & Simonini | B14a |
B. rubripes Thiers – see Caloboletus rubripes | |
B. satanas Lenz - misapplied to Rubroboletus eastwoodiae | |
B. satanus Lenz - misapplied to Rubroboletus eastwoodiae | |
B. smithii Thiers | B31c |
B. spadiceus Fr. | B18a, B42b |
= Xerocomus spadiceus | |
B. speciosus Fr. | B7a |
B. sphaerocephalus Barla - see Buchwaldoboletus sphaerocephalus | |
B. subglabripes Peck – see Hemileccinum subglabripes | |
B. subtomentosus Linne – see Xerocomus subtomentosus | |
B. truncatus (Singer & Snell & Dick) Pouzar - see Xerocomellus truncatus | |
B. variipes Peck | B12a |
B. zelleri (Murrill) Murrill - see Xerocomellus zelleri | |
BUCHWALDOBOLETUS Pilat | |
B. sphaerocephalus (Barla) Watling & T.H. Li | B26b |
= Boletus sphaerocephalus Barla | |
BUTYRIBOLETUS D. Arora & J.L. Frank | |
B. abieticola (Thiers) D. Arora & J.L Frank | B20b |
= Boletus abieticola Thiers | |
B. persolidus (Schaeffer) D. Arora & J.L. Frank | B19a |
B. autumniregius D. Arora & J.L. Frank | B7b |
B. primiregius D. Arora & J.L. Frank | B7b |
B. querciregius D. Arora & J.L. Frank | B7b |
CALOBOLETUS Vizzini | |
C. calopus (Pers.) Vizzini | B16a |
= Boletus calopus Pers. | |
C. conifericola Vizzini | B17b |
= Boletus coniferarum E.A. Dick and Snell | |
C. radicans (Pers.) Vizzini (sensu Kallenbach) | B17a |
= Boletus radicans Pers. (sensu Kallenbach) | |
C. rubripes (Thiers) Vizzini | B31a |
= Boletus rubripes Thiers | |
CHALCIPORUS J. Bataille | |
C. piperatoides (A.H. Sm. & Thiers) Baroni and Both | B23a, B33a |
= Boletus piperatoides A.H. Sm. and Thiers | |
C. piperatus (Bull.) J. Bataille | B23b, B33b |
= Boletus piperatus Bull. | |
CYANOBOLETUS Gelardi, Vizzini & Simonini | |
C. pulverulentus (Opat.) Gelardi, Vizzini & Simonini | B28b |   = Boletus pulverulentus Opat. |
FUSCOBOLETINUS Pomerl. & A.H. Sm. | |
F. aeruginascens (Secr.) Pomerl. and A.H. Sm.- see Suillus viscidus | |
F. laricinus (Berk.) A.E. Bessette, W.C. Roody, & A.R. Bessette - S. viscidus | |
F. ochraceoroseus (Snell) Pomerl. & A.H. Sm. | S8b |
F. viscidus (Linne) Grund and Harrison - see Suillus viscidus | |
GASTROBOLETUS Lohwag | |
G. imbellus Trappe | G3b |
G. ruber (Zeller) Cazares and Trappe | G4a |
= Truncocolumella rubra Zeller | |
G. subalpinus Trappe and Thiers | G3a |
G. turbinatus (Snell) A.H. Sm. and Singer | G4b |
G. vividus Trappe and Castellano | G2a |
GYROPORUS Quél. | |
G. castaneus (Fr.) Quél. | B40a |
HEMILECCINUM Šutara | |
H. subglabripes (Peck) Halling | B38a |
= Boletus subglabripes Peck | |
LECCINUM Gray | |
L. atrostipitatum A.H. Sm., Thiers, and Watling | L13a |
L. aurantiacum (Bull.) Gray | 16b, L18b |
L. brunneum Thiers | L9a |
L. clavatum A.H. Sm., Thiers, and Watling | L11a |
L. cretaceum (?) | L22b, Excluded species |
L. discolor A.H. Sm., Thiers, and Watling | L16b, 18b |
L. fallax A.H. Sm., Thiers, and Watling | L18a |
L. fibrillosum A.H. Sm., Thiers, and Watling | L19b |
L. holopus (Rostk.) Watling | L2a |
L. idahoense A.H. Sm., Thiers, and Watling | L6a |
L. incarnatum A.H. Sm. | L19a, Excluded species |
L. insigne A.H. Sm., Thiers, and Watling | L10a, 16b |
L. manzanitae Thiers | L11b |
L. ponderosum A.H. Sm., Thiers, and Watling | L6b |
L. roseofractum Watling | L22a |
L. rotundifoliae (Singer) A.H. Sm., Thiers, and Watling | L2b, 21a |
L. scabrum (Bull.) Gray | L21b |
L. subfulvum A.H. Sm., Thiers, and Watling | L5a, Excluded Species |
L. subtestaceum A.H. Sm., Thiers, and Watling | L10b |
L. testaceoscabrum (Secr.) Singer | L13b |
L. truebloodii A.H. Sm., Thiers, and Watling | L16a, Excluded Species |
Leccinum (undescribed) | L14a |
PORPHYRELLUS E.-J. Gilbert | |
P. porphyrosporus (Fr.) E.-J. Gilbert | B35a |
P. amylosporus A.H. Sm. - see Boletus amylosporus | |
PULVEROBOLETUS Murrill | |
P. ravenelii (Berk. & M.A. Curtis) Murrill | Summary, Description |
RUBROBOLETUS Kuan Zhao & Zhu L. Yang | |
R. eastwoodiae (Murrill) Vasquez, Simonini, Svetash., Miksik & Vizzini | B3a |
= Boletus eastwoodieae (Murrill) Sacc. & Trotter | |
R. haematinus (Halling) D. Arora & J.L. Frank | B4b |
= Boletus haematinus Halling | |
R. pulcherrimus (Thiers & Halling) D. Arora, N. Siegel & J.L. Frank | B4a |
= Boletus pulcherrimus Thiers and Halling | |
SUILLELLUS Murrill | |
S. amygdalinus (Berk. & M.A. Curtis) Murrill | 24b |
= Boletus amygdalinus (Thiers) Thiers | |
= Boletus puniceus Thiers | |
SUILLUS Gray | |
S. acidus (Peck) Singer | - see Nguyen et al. |
S. albidipes (Peck) Singer - see S. neoalbidipes | |
S. albivelatus A.H. Sm., Thiers, and Miller | S22a |
S. americanus (Peck) Snell ex Slipp & Snell | S13a, S18b, Excl. Species |
S. ampliporus (Peck) Kuntze | - see Nguyen et al. |
S. appendiculatus (Peck) A.H. Sm. & Thiers | S22b, Excluded Species |
S. borealis A.H. Sm., Thiers, and Miller | S20a |
S. brevipes (Peck) Kuntze | S14b, S33a |
S. brunnescens A.H. Sm. and Thiers | S20b |
S. caerulescens A.H. Sm. and Thiers | S6a |
S. cavipes (Opatowski) A.H. Sm. and Thiers | S8a |
S. clintonianus (Peck) Kuntze | - see Nguyen et al. |
S. elbensis (Peck) Kuntze | - see Nguyen et al. |
S. flavidus (Fr.) Singer | S13a, S14a |
= Suillus umbonatus Dick & Snell | |
S. flavogranulatus A.H. Sm., Thiers, and Miller | S31a |
S. fuscotomentosus A.H. Sm. and Thiers | S27a |
S. glandulosipes A.H. Sm. and Thiers | S21a |
S. granulatus (Linne) Kuntze | S28a, S31a |
S. grevillei (Klotzch) Singer | S12a |
S. helenae Thiers and A.H. Sm. | S31b |
S. imitatus A.H. Sm. and Trappe | S6b |
S. laricinus - see Fuscoboletinus laricinus | |
S. lakei A.H. Sm. and Thiers | S4a |
S. luteus (Linne) Gray | S11a |
S. neoalbidipes Palm & Stewart | S21b |
= S. albidipes (Peck) Singer | |
S. ochraceoroseus (Snell) Singer | S8b |
= Fuscoboletinus ochraceoroseus (Snell) Pomerl. & A.H. Sm. | |
S. pallidiceps A.H. Sm. and Thiers | S30a, S32a |
S. placidus (Bonorden) Singer | S30a, S32a |
S. ponderosus A.H. Sm. and Thiers | S5a |
S. pseudobrevipes A.H. Sm. and Thiers | S14b |
S. punctatipes (Snell and Dick) Snell & Dick | S29a |
S. ruber Singer & Sipe | S26b, Excluded Species |
S. sibiricus (Singer) Singer | S13a, 18a |
S. subolivaceus A.H. Sm. and Thiers | S12b |
S. tomentosus (Kauffman) Singer, Snell, and Dick | S25a |
S. tomentosus var. discolor A.H. Sm., Thiers, and Miller | S26a |
S. umbonatus Dick & Snell - see S. flavidus. | |
viscidus (L.) Roussel | S3a, S9a |
= Fuscoboletinus viscidus (L.) Grund and K.A. Harrison | |
= Suillus laricinus (Berk.) Kuntze | |
= Fuscoboletinus laricinus (Berk.) Bessette, Roody, & A.R. Bessette | |
= Suillus aeruginascens (Secr.) Snell | |
= Fuscoboletinus aeruginascens (Secr.) Pomerl. and A.H. Sm. | |
S. weaverae (A.H. Sm. & Shaffer) H. Engel & Klofac | - see Nguyen et al. |
TYLOPILUS P. Karst. | |
T. amylosporus (A.H. Sm.) A.H. Sm. - see Boletus amylosporus. | |
T. pseudoscaber (Secretan) A.H. Sm. and Thiers | S35a |
XEROCOMELLUS | |
X. chrysenteron (Bull.) Šutara | B43a |
= Boletus chrysenteron (Bull.) Fr. | |
X. rainisiae (Bessette & O.K. Mill.) N. Siegel, C.F. Schwarz & J.L. Frank | B28a |
= Cyanoboletus rainisiae (Bessette & O.K. Mill.) Gelardi, Vizzini & Simonini | |
= Boletus rainisiae Bessette & O.K. Mill. | |
X. truncatus (Singer, Snell & E.A. Dick) Klofac | B44a |
= Boletus truncatus Singer, Snell & E.A. Dick | |
X. zelleri (Murrill) Klofac | B37a |
= Boletus zelleri (Murrill) Murrill | |
XEROCOMUS Quél. | |
X. subtomentosus (Linne) Quél | B42a |
= Boletus subtomentosus (L.) Quel. |
- END -