Summary:
The outstanding features of Chlorophyllum olivieri are 1) large gray-brown to tan or light brick brown scales on a pale cap with a brown center, not contrasting as much as Chlorophyllum brunneum, 2) free white gills that easily bruise orange to pinkish, 3) prominent double-edged ring, 4) a swollen to abruptly bulbous base of the stem, 5) bruising of flesh to pinkish red, and when scraped, turning orange or pinkish or red, 6) growth most often in rich leaf litter and forest humus in disturbed areas, and 7) microscopic characters including balloon-shaped cheilocystidia with a narrow neck, and spores with a germ pore. Vellinga recognizes this species as resembling Chlorophyllum rhacodes (= Macrolepiota rhacodes var. rhacodes) in general habit, but differing in the olivaceous drab, gray or brownish scales that do not contrast with the background, and the slightly smaller spores, being widespread in Europe (spruce and deciduous woods), and from oak habitats in the Pacific Northwest. According to Vellinga(3), illustrations include those for Macrolepiota rachodes var. rachodes in Breitenbach(4), and for Lepiota rhacodes in Phillips(2) - Mushrooms and other fungi of Great Britain and Europe. The descriptions given with these illustrations are used below in addition to the one from Sieger(1).

Cap:
7-14(18)cm across, spherical when young, expanding to flat, not umbonate; "surface in the center smooth and dark red-brown, splitting up from the margin inward into concentric, brown, prostrate to erect, flat scales, the cream-colored trama somewhat showing through when young, +/- evenly gray- to olive-brown when old, margin obtuse, fibrillose-floccose", (Breitenbach), 5-15cm across, ovate then expanding to almost flat; "disrupting into broad, pallid, often slightly reflexed scales on fibrous background, giving the cap a shaggy, torn appearance", (Phillips), 5-12cm across, convex becoming flat with umbo when old; disc grayish olive brown, smooth, margin colored like disc but soon breaking up into coarsely fibrous scales on a dingy background, (Sieger), cap scales of similar color to background (often olivaceous brown, grayish brown), (Vellinga)

Flesh:
thick in center, thin toward margin; whitish, immediately turning orange-saffron-yellow when cut, then pink and finally red-brown, in stem discoloring like the cap flesh when cut, (Breitenbach), "white becoming orange to carmine red on cutting", (Phillips), cut flesh in stem staining reddish or saffron, (Sieger)

Gills:
free, broad, close, soft; white to cream "but easily bruised and turning light orange to pinkish", (Siegel), free, 85-110 reach stem, broad, 3-7 subgills between each set of gills; white when young, then cream and spotting pink; edges "whitish when young, later brown-floccose", (Breitenbach), white, tinged reddish when older, bruising reddish, (Phillips), free, close, in two or three tiers; white becoming red or brown when bruised, darkening when old; edges finely fringed, (Sieger)

Stem:
8-20(25)cm x 0.8-1.5cm at top, up to 4cm wide at bulb, cylindric, straight, tall and slender "but with a distinctly swollen to abruptly bulbous base"; stem white to light beige, "developing tan tones"; smooth, dry; base "often with copious cottony mycelium and adhering substrate", (Siegel), 9-16(18) x 1.2-1.6(2)cm, cylindric, "enlarged toward the base, base sometimes bent and bulbous to marginate-bulbous and white-tomentose, rigid, fragile, hollow, surface above the annulus whitish and smooth to longitudinally fibrillose, surface below it whitish and spotting red-brown to brown when touched, gray- to ocher-brown when old", (Breitenbach), 10-15cm x 1-1.5cm, widening toward the bulb which is usually oblique; "whitish tinged dirty pinkish-brown, bruising reddish brown when fresh", (Phillips), 7-15cm long, about 1 1/2 times as long as the diameter of the cap, 0.7-1.5cm wide, equal with abruptly bulbous base, stuffed; white, darkening when bruised, (Sieger)

Veil:
forming "a flaring ring with a shaggy, double edge, often grayish tan to brown on underside and edge", (Siegel), ring "membranous, cream-white, with a jagged margin, movable", (Breitenbach), double, membranous, movable on stem, (Phillips), thick, persistent, membranous, double ring, movable, white with lower surface darkening when old, edge fibrous and frayed, (Sieger)

Odor:
"mild or pleasantly earthy" (Siegel), faintly like raw potatoes, (Breitenbach), strongly aromatic (Phillips), not remarkable (Sieger)

Taste:
mild (Siegel), mild, nutty, (Breitenbach), pleasant (Phillips), not remarkable (Sieger)

Microscopic spores:
spores 8-11 x 5.5-7 microns, elliptic, ''with a small indented "thumbprint"-like germ pore''; cheilocystidia balloon-shaped "with a very narrow base, sometimes with additional inflated cells near base", (Siegel), spores (7.5)8.0-11.0 x 5.5-7.0 microns (average 8.7-10.0 x 5.8-6.6 microns) as compared to 8.8-12.7 x 5.4-7.9 microns (average 9.5-10.7 x 6.2-7.4 microns) for C. rhacodes, (Vellinga), spores 8.8-11.2 x 6.8-8 microns, elliptic-oval, smooth, dextrinoid, colorless, thick-walled, with an indistinct germ pore; basidia 4-spored, 33-39 x 9-12 microns, clavate, with basal clamp connection; pleurocystidia not seen, cheilocystidia 21-47 x 12-20 microns, clavate to pyriform; septa without clamps in cap cuticle but clamps on many septa especially in hymenium, (Breitenbach), spores 10-12 x 6-7 microns, elliptic with germ pore, dextrinoid, (Phillips), spores 8-10.5 x 5-6.5 microns, oval, dark reddish brown in Melzer''s (dextrinoid), with small germ pore; pleurocystidia absent, cheilocystidia clavate, not strangulated, (Sieger)

Spore deposit:
white (Siegel), pale yellow (Breitenbach), white (Phillips)

Notes:
Chlorophyllum olivieri is often found on foray lists in WA and BC and there is a collection from BC at the University of British Columbia.

EDIBILITY

edible and good, but Chlorophyllum "can cause gastrointestinal upsets due to allergic reactions, so be sure to eat only fresh specimens, cook them thoroughly, eat only a small amount the first time, and make sure it''s not C. molybdites!" (Siegel), edible and choice, but may sicken some people (Sieger), there are reports of severe gastrointestinal reactions to Chlorophyllum from regions where Chlorophyllum molybdites does not occur, (Benjamin), make sure it is not Chlorophyllum molybdites!