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

Summary:
Features include 1) a slightly viscid to dry cap that is bright yellow (or at times more brownish) with bright yellow upcurved scales, 2) bright yellow gills that become brown along the edges when rubbed, 3) a bright yellow stem (or the base slightly darker) with yellow upcurved scales, 4) growth on rotten conifer wood, and 5) microscopic characters including small spores. Trudell(4) says it is fairly common in the Pacific Northwest.

Smith(3) examined collections from WA, OR, ID, CO, ME, MI, NC, NY, and TN. There are multiple reports from BC (Redhead(5)). It has also been reported from QC (Lincoff), CA (Desjardin), and AK (Miller). Breitenbach(4) give the distribution as North America, Europe, and Asia.

Cap:
3-8(10)cm across, convex or obtuse becoming broadly umbonate to nearly flat; "brilliant yellow or at times dark yellow or tawny at center", covered with bright yellow scales that may wear off when old; "dry or in wet weather sometimes viscid beneath the scales", "margin usually fringed with veil remnants", (Arora); (3)4-8(10)cm across, "obtusely conic becoming broadly umbonate, at time the umbo obsolete"; brilliant yellow ("picric yellow") overall including the veil remnants, at times "lemon-chrome" to "deep-chrome" or "raw sienna", disc at times tawny when old; "viscid beneath a covering of recurved fibrillose scales", becoming bald at times when old, "the margin often fringed with veil remnants as a thin sheet or in patches", (Smith), brilliant yellow to orange-yellow (Trudell)

Flesh:
fairly firm; yellow, (Arora), thick, firm, pliant; yellow and with greenish yellow line next to gills; in stem colored as cap, (Smith)

Gills:
usually adnexed or notched, spacing close; bright yellow becoming rustier when old, (Arora), sharply adnexed, close to crowded, moderately broad to broad when old, 3 tiers of subgills; "picric-yellow", staining dingy brown along edges when rubbed; edges even, (Smith)

Stem:
(3)5-10cm x 0.4-1cm, equal or slightly wider at base; bright yellow or base slightly darker; smooth above veil, sheathed with dense layer of yellow recurved [upcurved] scales in lower part, not viscid, (Arora), (3)5-10(12)cm x (0.3)0.5-1cm, equal or slightly widened at base, solid, stuffed to hollow; colored as cap, darkening to cadmium yellow at base; covered up to the ring with dense coating of recurved yellow scales from ruptured veil, silky fibrillose above ring, (Smith)

Veil:
"bright yellow, disappearing or forming a slight superior ring or fibrillose-cottony zone on stalk", (Arora), veil "forming an evanescent, superior zone of bright yellow fibrils or submembranous", (Smith)

Odor:
mild (Smith, Miller), unpleasant (Schalkwijk-Barendsen), fruity (Kibby)

Taste:
mild (Smith, Miller), rather peppery unpleasant (Kibby)

Microscopic spores:
spores 3-5 x 2-3 microns, oblong to elliptic, smooth, chrysocystidia on gills, (Arora), spores 4-5 x 2.5-3 microns, oblong to elliptic, smooth, thin-walled, no germ pore seen, ochraceous in KOH and about the same color in Melzer''s reagent; basidia 4-spored, 18-22 x 3.5-4.5 microns, narrowly clavate, colorless in KOH, yellowish in Melzer''s reagent; pleurocystidia of 2 types 1) 25-35 x 6-8 microns, "clavate to mucronate and with a dark flavous homogeneous content as revived in KOH, in Melzer''s reagent yellowish", walls smooth, thin and colorless, 2) chrysocystidia 26-40 x 6-9 microns, fusoid-ventricose to clavate-mucronate, content amorphous and granular-aggregated to form folded (reticulate) masses cinnabar to orange-brown in Melzer''s reagent, cheilocystidia as in type 1 of pleurocystidia or small and cylindric, (18-20 x 3 microns), the former abundant; clamp connections present, (Smith)

Spore deposit:
brown (Arora, Miller)