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Summary: Features include dry whitish cap that is smooth or fibrillose and quickly stains amber to yellow-orange when bruised; thick flesh that usually bruises yellow if crushed; free close gills that are pallid to grayish or grayish pink then chocolate-brown or blackish brown; white stem that is smooth in upper part and may be slightly cottony-scaly in lower part; skirt-like ring that often has cottony patches underneath that may form cogwheel pattern; strong almond or anise odor; and growth in woods. It is found at least in WA, AK, (Isaacs), OR (Zeller), and CA (Kerrigan, Zeller). There are collections from BC deposited at University of British Columbia., CHEMICAL REACTIONS cap surface staining yellow in KOH (Arora)
Cap: 7-18cm across, convex to flat; white at first "but quickly staining amber to yellow-orange when bruised and often entirely yellowish to yellow-orange to amber or ochraceous in age"; "usually dry, smooth or fibrillose", margin often has hanging veil remnants, (Arora), 7-12(17)cm across, broadly convex becoming almost flat; "fibrils white, or very faintly buff (especially on disc)", surface becoming bright orange-yellow when bruised or cut, yellowish on drying; dry, fibrillose, when old "forming broad, loosely interwoven fibrillose patches", (Kerrigan), viscid when wet (Zeller)
Flesh: thick; "white, usually bruising yellowish if crushed", flesh in base not usually bruising bright yellow, but exterior of base may, (Arora), up to 1.5cm thick; white, becoming yellowish when cut, in stem white becoming yellowish when exposed, (Kerrigan)
Gills: free when mature, close; "pallid becoming grayish or grayish-pink, then eventually chocolate-brown or darker", "often bruising yellow when immature", (Arora), free, close, 0.6-1cm broad; pallid to grayish-pink, eventually dark blackish brown, (Kerrigan)
Stem: 5-14cm x 1.5-3cm, usually with widened base (up to 5cm wide), firm; white or discoloring yellowish, exterior of base may bruise yellow; smooth above ring, smooth or slightly cottony-scaly below ring, (Arora), 4-9cm x 2-2.5cm, equal above bulbous base, up to 3(4.5)cm wide at base, stuffed-hollow; smooth or finely striate in upper part, subglabrous [nearly bald] or with a few obscure fibrils in lower part, (Kerrigan)
Veil: membranous, white or yellow-stained, with patches on underside that sometimes form a cogwheel pattern, forming an ample, superior, skirt-like ring on stem, (Arora), forming thin, broadly flaring, subapical to supramedian, pendant white ring, "upper surface smooth, lower surface somewhat floccose", (Kerrigan), double ring (Chariton)
Odor: strongly sweet and anise-like or almondy (Arora), almond (Kerrigan), older specimens disagreeable, like wet straw, (Chariton)
Taste: pleasant, almond-anise, (Chariton), weakly of anise, musty when dry, (MykoWeb)
Microscopic spores: spores 5-7 x 3.5-4.5 microns, elliptic, smooth, (Arora), (4.8)6.3-6.5(7.5) x (3.8)4.3-4.7(5.3) microns, elliptic, dark brown, hilar appendix not prominent, germ pore not evident; basidia 4-spored, 18-21 x 7.5-8.5 microns, clavate; cheilocystidia, 12-24 x 4.5-6 microns, "cylindric to short cylindroclavate, or possibly basidiole-like, few; lamellar margin largely fertile", (Kerrigan)
Spore deposit: chocolate brown (Arora)
Habitat / Range
single, scattered or gregarious on ground in woods, (Arora), single to somewhat gregarious under Quercus (oak) or under conifers, (Kerrigan for California)
A. albolutescens is like Agaricus silvicola but squatter (more robust), with a much stronger odor (sweet and anise-like or almondy), and the cap stains amber, (Arora). A. albolutescens compared to A. silvicola is shorter and has a much stronger tendency to become yellow; it also has slightly larger spores and apparently fewer cystidia than A. silvicola, (Kerrigan). Agaricus xanthoderma stains bright yellow in the base of the stem, has a phenol odor, and eventually discolors brownish after staining yellow, (Arora). A. xanthoderma stains fleetingly yellow (fading within minutes), while A. albolutescens bruises slowly but persistently yellow, and A. xanthoderma has a phenolic or medicinal odor, (MykoWeb). Agaricus arvensis is somewhat similar but A. albolutescens grows in woods rather than open grassy places (Arora), and the color is different especially when dry as A. albolutescens becomes entirely yellow. Agaricus flavitingens is similar, as Zeller says, "There is some similarity to A. flavitingens Murrill, but the type of the latter is not available." (Zeller).
Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2019. E-Flora BC:
Electronic Atlas of the Plants of British Columbia [eflora.bc.ca]. Lab for
Advanced Spatial Analysis, Department of Geography, University of British
Columbia, Vancouver. [Accessed:
2020-02-28 11:26:04 AM
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