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

Summary:
Clade Brevipes. Russula brevipes group is recognized by the dull white color of the fruitbodies, a centrally depressed cap with an inrolled margin when young, a hard stem, and crisp flesh that does not blacken or redden when bruised, (Arora). Other features are large size, a dry surface, crowded, white gills that may stain brown, mild or slightly peppery taste, white to cream spore deposit, and growth in woods or open places. |Russula brevipes group is often parasitized by the orange Hypomyces lactifluorum. |There is evidence for at least 5-6 species in this group in the Pacific Northwest, most only separable by DNA, with none being the true Russula brevipes (described from eastern North America) or the true Russula chloroides (described from Europe), (D. Miller, pers. comm.). |Var. acrior has a bluish green tinge in the gills near the stem and at the top of the stem, and often has a more intensely peppery taste. According to D. Miller (pers. comm.) the blue pigment and acrid taste of var. acrior does not seem to be confined to a single Pacific Northwest species. |Russula brevipes var. megaspora Shaffer [spores 9.3-14.1 x 8-12 microns] has supporting DNA evidence for its presence in the Pacific Northwest, (D. Miller, pers. comm.) Morphological features need to be correlated. |Russula brevipes group are the commonest of the larger Russulas in the Pacific Northwest. |The name Russula delica has been used in the past for what has more recently been known as Russula brevipes.

Russula brevipes group are found in BC (Gamiet). Shaffer examined collections from WA, OR, ID, CA, NS, ON, CO, IN, MA, ME, MI, NH, NM, NY, TN, TX, VT, and WY, the type variety being represented by WA, OR, ID, CA, CO, MI, NH, NY, VT, and WY, and var. acrior by OR, ID, MA, MI, NM, and VT. Thiers gives both varieties for CA as well as var. megaspora. G. Laursen extended this range for R. brevipes to AK, MT, and VA (collections at the University of Washington).

Cap:
8-20cm across, dimpled when young becoming broadly funnel-shaped, margin inrolled when young; "white to buffy white with yellow brown stains"; matte, even, cap skin not peeling, (Woo), 7.6-12.7cm across, convex, umbilicate, becoming centrally depressed or funnel-shaped; "white or whitish, often with yellowish or rusty yellow stains or patches in the center"; dry, bald or nearly so, (Peck), 9-20cm across, when young depressed on disc and with inrolled margin, expanding to broadly funnel-shaped; "white to buffy white, but soon stained with dull yellow or brown" and at times becoming brownish overall when old; dry, matte, minutely felted, at times radially rugulose [wrinkled], not striate, (Shaffer), 7-30cm across, "broadly convex with a depressed center and inrolled margin", becoming broadly vase-shaped when old; "white or whitish but often dirty and/or with yellowish to brown stains and discolorations"; "dry, unpolished, minutely woolly or felty", margin not striate, (Arora)

Flesh:
hard, brittle; white, (Woo), whitish (Peck), thick, 0.7-2cm in disc, hard-brittle; white, often stained with brown around larva channels, (Shaffer), "thick, crisp, brittle"; white, not staining, (Arora)

Gills:
crowded, abundant subgills, narrow; white, becoming stained yellow brown; "often beaded with drops of clear liquid when fresh", (Woo), adnate or decurrent (rarely slightly rounded at stem), close, thin; white becoming tinged with pale cinnamon or ferruginous when old or in drying, (Peck), decurrent, usually close (occasionally crowded), with abundant subgills of varying lengths, gills narrow, 0.3-0.9cm broad, thin, acute near margin, sometimes forked near stem; nearly white when young, becoming pale yellow, at times "pale olive-buff" [Ridgway(1) color] when old, becoming spotted-stained with cinnamon to clay color; interveined, (Shaffer), adnate to decurrent, close or crowded, thin, usually alternating long and short; white or creamy (but tinged blue-green in var. acrior), often brownish-stained when old, (Arora)

Stem:
short, stout; white staining brown, (Woo), 2.5-5cm long, firm, solid; white; bald, (Peck), 3-8cm x 2.5-4cm, equal or narrowing slightly at base, straight, round in cross-section, solid or becoming hollowed by larvae; white, sometimes becoming stained with brown; unpolished, rugulose [wrinkled], (Shaffer), 2-7(10)cm x 2-5cm, equal or narrowing downward, hard and rigid, often quite short and stout; dull white or brownish-stained, sometimes with blue-green tinge at top (var. acrior); smooth, dry, (Arora)

Odor:
slight, sometimes faintly disagreeable, (Shaffer)

Taste:
mild or slightly peppery (Woo), mild or slightly and tardily peppery (Peck), mild to slightly peppery (Shaffer), mild or slowly peppery, (Arora)

Microscopic spores:
spores 9-12 x 8-10 microns, ornamentation Patterson-Woo type C-3, (Woo), spores round, 10-12.5 microns broad, (Peck), spores 9-11 x 8.5-10 microns, warts 1.0-1.7 microns high, "with a continuous or broken reticulum of fine lines", (Hesler(5)), spores 8.0-10.6 x 6.7-8.6(9.8) microns excluding ornamentation, usually broadly elliptic, occasionally broadly ovate, broadly obovate, or nearly round, rarely round, ornamentation 0.7-1.7 microns high, of cylindric to conic, blunt-tipped to acute-tipped, "occasionally partially nonamyloid warts which may be almost completely isolated, but which on most spores are usually aligned or connected by fine to moderately heavy lines, the ornamentation then forming a broken to nearly complete reticulum"; basidia 4-spored, 49-67 x 8.6-13.3 microns, usually clavate, rarely fusiform; pleuropseudocystidia abundant, 43-94 x 6.7-13.3 microns, projecting to 27 microns beyond the basidioles, arising in the subhymenium or trama, clavate to fusiform, "sometimes capitate, submoniliform near the apex, or bearing a stub, otherwise rounded to subacute apically", "straight, curved, or flexuous basally", "filled partially to completely with granular to linear, refractive, yellowish contents", cheilopseudocystidia common to abundant, 33-81 x 6.0-12.0 microns, like the pleuropseudocystidia; cap cuticle 67-186 microns thick, lacking a gelatinous matrix, of interwoven to generally horizontally oriented, non-gelatinous, septate, branched, colorless to yellowish brown hyphae 1.3-6.7 microns wide which may give rise to scattered or tangled-clustered, ascendant to erect, undifferentiated hairs to 140 microns long, oleiferous hyphae absent to fairly common, (Shaffer), spores 8-11 x 6.5-9 microns, elliptic, with amyloid warts and ridges, (Arora)

Spore deposit:
white to pale cream, Crawshay B, (Woo), white to light cream color, lighter than Crawshay B, even when colored, almost white in thin deposits, (Shaffer), white to pale buff (Arora), normally cream rather than white, although paler than R. cascadensis (D. Miller, pers. comm.)