E-Flora BC: Electronic Atlas of the Flora of British Columbia

Suillus sibiricus (Singer) Singer
Siberian slippery jack

Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.

Introduction to the Macrofungi

© Edward Lum  Email the photographer   (Photo ID #65245)

E-Flora BC Static Map
Distribution of Suillus sibiricus
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Species Information

Features include 1) a viscid yellow cap with reddish to brown spots, streaks or plaques, 2) pale olive-yellow flesh that turns dull cinnamon or vinaceous when cut, 3) large, angular compound pores that stain dull cinnamon when bruised, 4) a yellowish stem that has brown to cinnamon glandular dots and smears and stains vinaceous or brown when handled, and 5) a veil that leaves remnants hanging from cap margin and sometimes forms a slight annulus. Suillus sibiricus is found in WA, OR, and ID, (Smith(34)). It is also found in BC (collections at the University of British Columbia), CA (Arora; collection at Oregon State University), AK, MT, and WY (collections at the University of Washington), and MI (Smith(35)). Distribution is eastern Canada south to NY, west to the Pacific Northwest, and also (reported from) the Southwest, (Bessette).
3-10cm, obtuse to convex, becoming broadly convex to nearly flat when old, sometimes slightly umbonate; ground color dull to bright yellow or ocher-yellow to olive-yellow, scattered appressed scales dull reddish to cinnamon-brown or dark brown; viscid to glutinous; margin with hanging tufts of whitish cottony veil that may disappear when old, (Bessette), 3-10cm, convex to obtuse, expanding to flat or slightly umbonate; ground color "chamois" (Ridgway color) to dingy olive-yellowish, "spotted overall but especially toward the margin with snuff-brown to cinnamon-brown appressed squamules"; viscid to glutinous; "margin at first a with soft cottony roll of pale dingy yellow veil remnants", or the roll often breaking up into teeth and finally disappearing, (Smith(34)), "with scattered reddish to cinnamon-brown or dark brown spots, scales, streaks, or patches of fibrils, especially toward the margin (but these sometimes washed off by rain)", "cap is usually bright yellow in dry weather and duller or dingier when moist", (Arora)
pale olive-yellow, slowly staining dull cinnamon when exposed, not turning blue, (Bessette), pale olive yellow, slowly becoming dull cinnamon when cut; in stem dingy olive-yellowish, (Smith(34)), thin, soft; yellow, not turning blue but often staining vinaceous or pinkish when bruised, (Arora)
1-2mm, angular and compound; yellow to dingy ocher-yellow, "staining dull cinnamon when bruised"; tube layer 0.8-1.5cm thick, adnate to subdecurrent, (Bessette), 1-2mm, "angular and often compound", dingy ocher-yellow, "staining dull cinnamon when bruised"; tube layer 1-1.5cm thick, adnate becoming decurrent, dingy ochraceous to near "honey yellow" (Ridgway color), (Smith(34)), 1-2mm when mature, often somewhat radially arranged; mustard-yellow becoming duller or darker (ocher to yellow-brown) when old, not turning blue but may stain vinaceous or pinkish; tubes same color or dingier, (Arora)
4-10cm x 0.6-1.5cm, nearly equal or narrowing downward, solid; yellow to dingy ocher-yellow, often stained vinaceous near base; "with reddish to dark brown glandular dots and smears", dry; partial veil cottony, whitish, typically leaving remnants on cap margin, sometime forming slight annulus on stem, (Bessette), 5-10cm x 0.7-1.5cm at top, solid; dingy ocher yellow in upper part, "soon stained vinaceous at base"; "glandular dotted overall"; occasional specimens with annulus but partial veil typically hanging on cap edge, (Smith(34)), often curved, solid or sometimes hollow when old; yellow to ocher-yellow, often staining vinaceous or brown when handled and often vinaceous-stained at base; glandular dots and smears often inconspicuous when young but typically brown to cinnamon and quite conspicuous when old; veil cottony, whitish to pale yellow or when old sometimes brownish, usually remaining attached to cap margin but sometimes forming slight annulus, (Arora)
not distinctive (Bessette), none or slight (Smith(34)), distinctive (Phillips)
acidic or not distinctive (Bessette), acidulous (Smith(34)), mildly bitter (Phillips)
spores 8-11 x 3.5-4.2 microns, narrowly elliptic, smooth, pale ochraceous, (Bessette), spores 8-11 x 3.8-4.2 microns, narrowly elliptic, smooth, pale tawny to yellowish in Melzer's reagent, pale dingy ochraceous in KOH; basidia 4-spored, 22-28 x 5-7 microns, clavate, nearly colorless in KOH; pleurocystidia 40-70 x 6-9 microns, "cylindric to narrowly clavate and often crooked, content of yellow to dark brown pigment", in bunches surrounded by brown amorphous pigment, cheilocystidia "similar to pleurocystidia, many somewhat ventricose", masses of amorphous pigment encrusted on wall end; cap epicutis "a pellicle of appressed-interwoven hyphae" 3-6 microns wide; caulocystidia similar to cheilocystidia; clamp connections absent, (Smith(34)), spores 8-12 x 3.5-4.5 microns, elliptic to spindle-shaped, smooth, (Arora)
Spore Deposit:
dull cinnamon, (Bessette), "Sayal brown" (Ridgway color), (Smith(34)), brown to dull cinnamon-brown (Arora)

Habitat / Range

scattered or in groups under pine and larch, (Bessette), gregarious under Pinus monticola (Western White Pine), (Smith(34)), scattered to gregarious or clustered under conifers, associated with white (5-needle) pines, especially common in Pacific Northwest and northern California with Western White Pine, in Southwest with southwestern white pine and limber pine, (Arora), fall

Taxonomic and Nomenclatural Links

Additional Range and Status Information Links


yes (Bessette), yes, but A.H. Smith reports a case of acute allergic reaction by merely touching it, (Arora)

Additional Photo Sources

Related Databases

Species References

Smith(34), Smith(35), Bessette(3)*, Arora(1)*, Trudell(4)*, Thiers(1), Phillips(1)*, Both(1)

References for the fungi

General References