Amanita silvicola
western woodland amanita
Amanitaceae

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

Introduction to the Macrofungi

Photograph

© Michael Beug     (Photo ID #15303)


Map

E-Flora BC Static Map

Distribution of Amanita silvicola
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Species Information

Summary:
Subgenus Lepidella. Features are white color; stout stature for an Amanita; white, powdery or cottony patches on the cap (unless washed off by rain); enlarged stem base; and mild to soapy to fishy odor. Amanita silvicola is common in the Pacific Northwest.
Cap:
5-12cm across, convex to flat; white (occasionally discolored when old); "covered with flattened cottony or fluffy-powdery patches" of universal veil tissue rather than warts, "dry or slightly viscid when moist", non-striate, often hanging margin remnants present and margin often extends past gills, (Arora), margin often incurved (Phillips)
Flesh:
white (Arora), quite thick (Phillips)
Gills:
adnate to adnexed or free, close; white; "edges finely powdery or cottony", (Arora)
Stem:
5-12cm x 1.5-2.5cm, usually rather stout, with basal bulb up to 5cm; stem white sometimes with brown stains; powdery or with cottony scales, (Arora), 6-10cm x 1-2.5cm, solid, narrows slightly downward at the top, rarely rooting, (Phillips), VOLVA universal veil "cottony, white, forming a scaly or indistinct volva consisting of cottony white zones or patches at base of stalk which often disintegrate or remain in the ground", (Arora), fragile, white, "clinging to bulb in fragments and breaking up into circular zones but often adhering to the earth", (Goetz, D.)
Veil:
partial veil "white, delicate, forming a slight ring or fibrillose zone or disappearing", (Arora)
Odor:
mild or slightly soapy (Arora), fishy when old (Lindgren)
Taste:
not distinctive (Lindgren)
Microscopic spores:
spores 8-12 x 4.5-6 microns, elliptic, smooth, amyloid, (Arora)
Spore deposit:
white (Arora)
Notes:
It is reported specifically for BC (in Redhead(5)), for WA by O''Dell(1), and for CA by Arora(1). Collections from OR are at Oregon State University.
EDIBILITY
unknown, do not eat, especially because of resemblance to poisonous Amanita smithiana

Habitat and Range

SIMILAR SPECIES
Amanita smithiana is somewhat similar with its white color and ragged or shaggy stem, but in A. smithiana 1) the stem is more likely to be rooting and spindle-shaped (as opposed to marginate or clavate), 2) the odor may be unpleasant, 3) warts are formed on cap rather than patches (but may not be distinct), 4) stature is usually taller in relation to width than for A. silvicola, 5) clamp connections are present on basidia, 6) spores are somewhat smaller, 7) it lacks chains of inflated cells in universal veil remnants on cap, and 8) there is a positive chemical reaction of cut stem to syringaldazine and to paracresol.
Habitat
single or in small groups in coniferous or mixed woods, (Arora), especially under Douglas fir; fruiting September to October, (Phillips), fall