Farmscape Eccology Program

a Hawthorne Valley Association Program

Oysters & Oyster-like Mushrooms

Link back to Polypores, Brackets & Oysters page

Oyster and oyster-like mushrooms are “pleurotoid,” where kidney-shaped or semicircular caps with gills are attached laterally and directly out of the wood, with or without a stem. They often fruit in groups or clusters, sometimes with stems fused at the base. They are not technically brackets but many of them form shelves similarly.

True Osyters (Pleurotus spp.)

Brown-spored Oysterlings (Crepidotus spp.)

Other Oyster-like Mushrooms

 

True Osyters (Pleurotus sp.)

Oyster Mushroom (Pleurotus ostreatus complex)

Notes: This North American complex also contains the Pale or Summer Oyster, Pleurotus pulmonarius and Pleurotus populinus. Season and habitat help to differentiate them but they are very similar and can have some seasonal overlap. All Pleurotus species are edible with caution. Some people find that even these edible oyster mushrooms give them a mild allergic reaction. When trying new wild mushrooms, its always good to try a small amount, make sure there is no bug damage, and thoroughly cook.

Habitat & Ecology: saprophytic; logs and trunks of dead and alive deciduous trees, especially elm; P. ostreatus fruits in the cooler time of the year, P. pulmonarius fruits in the summer, and P. populinus fruits spring to fall and mostly on aspens and cottonwood

Cap: fan-shaped, convex at first and becoming flat; smooth; margin becomes wavy; P. ostreatus (first pair of images) is light brown and sometimes ashy; P. pulmonarius (last two images) and P. populinus are lighter colored; dry

Gills: decurrent gills; close; thick; white, browning edges with age 

Stem: cap is laterally attached to the substrate with or without a stem or pseudostem; white of the gills; smooth; dry

Flesh: white; pleasant, oysters have a distinct smell that is a bit fishy

Spore print: light-spored; P. ostreatus white, lilac, or faint yellow; P. populinis has a white print; P. pulmonarius can be white, gray or lilac

Look-alikes: 

Golden Oyster (Pleurotus citrinopileatus)

Notes: This species is a non-native, escaped cultivar which fruits prolificially in the wild. When trying new wild mushrooms, its always good to try a small amount, make sure there is no bug damage, and thoroughly cook. Some people find that even these edible oyster mushrooms give them a mild allergic reaction.

Habitat & Ecology: saprophytic; large groups and clusters on hardwood logs and standing trunks, especially elm; summer and fall

Cap: convex or trumpet-shaped with a depression in the center that can become quite deep; smooth, sometimes with grey dust around the depression;  inrolled margin when fresh, becoming wavy; bright yellow, not orange; dry

Gills: decurrent, almost going all the way down the stem; subdistant; white; short gills frequent 

Stem: might taper towards the bottom, bases often fused in a white mass; white; ribbed from gills; dry

Flesh: pale yellow/white; pleasant, oysters have a distinct smell that is a bit fishy

Spore print: pale pink

Look-a-likes: The Honey Mushroom (Armillaria mellea) can look similar (yellow caps and fused bases) but their caps have scurfiness on them and the gills are not decurrent; the Jack o’ Lantern mushroom (Omphalootus iludens), is a well-known poisonous mushroom which grows in dense clusters at the base of trees or on buried stumps, is orange and has orange flesh, and the gills are very crowded.

 

Brown-spored Oysterlings (Crepidotus)

  • Smaller than the true oysters 

  • Have brown spore prints

 

Flat Crep (Crepidotus applanatus group) 

Notes: this group also includes Crepidotus malachius (need microscopic characters, like spore size, to distinguish it) and Crepidotus alabamensis (southeastern species)

Habitat & Ecology: saprophytic; hardwood logs and stumps; summer to fall

Cap: convex to flat; large caps (between 1-4cm wide) shaped like spatulas or small shells and growing in groups; smooth surface, hygrophanous (becoming translucent with moisture); lined margin at maturity; white or off-white but becoming pale brown; frosty bloom at the base of the cap; dry

Gills: broadly attached, almost decurrent; close to crowded; white and slowly becomes brown but not uniformly; cap laterally attached to wood; white; hairy near attachment; dry

Flesh: white and soft

Spore print: brown

Look-alikes:  Crepidotus pini is found on Scots Pine wood; Pleurotus ostreatus group has light-colored spore prints, are usually larger, often with more of a stem and the gills are thicker and a bit more spaced out; Angel’s Wings (Pleurocybella porrigens) grow on conifers, have an extended base, white spore print, and the gills don’t turn brown; Hohenbuehelia angustata is on hardwood, has an extended base, a brownish cap, super close gills, and a white spore print.

Saffron Crep (Crepidotus crocophyllus)

Notes: Young specimens are best for ID, the fibrils and orange gills can be variable

Habitat & Ecology: saprophytic; deciduous logs; late spring to fall

Cap: semi-circular or kidney-shaped; margin entire and curved in at first; soft yellow or dull brown underneath a carpet of brown fibers that split into bundled tufts with dark speckles that highly contrast the cap; dry 

Gills: pastel orange to bright yellow; close to crowded spacing and overall shallow

Stem: no stem but there is a fuzzy white patch at the base

Flesh: soft, thin, and white; smell not distinctive

Spore print: brown

Look-a-likes: Crepidotus calolepis, in the Crepidotus mollis group, has a scaly cap too but they have white or brownish gills, not orange, and is rubbery; Stinking Orange Oyster (Phyllotopsis nidulans) _____…

Peeling Crep or Oysterling (Crepidotus mollis group)

Notes: This group includes three species, Crepidotus mollis and Crepidotus calolepis (synonym C. mollis var. calolepis), and Crepidotus kauffmanii. 

Habitat & Ecology: saprophytic; deciduous wood; later spring to fall

Cap: fan-shaped caps; hygrophanous and pale yellow; C. mollis surface is bald and C. calolepis has dark scales; margin curved in and slightly lined at maturity; when moist, there is a layer of gelatinous material that can be peeled off the cap; dry 

Gills: gathers at point of attachment; close to crowded, and thin; white and slowly becomes brown but not uniformly; cap laterally attached to wood;   

Flesh: made up of gelatinized hyphae, so the flesh is rubbery

Spore print: 

Look-a-likes: C. kauffmanii in the group does not have a gelatinous layer on the cap that can be peeled; Saffron Crep, Crepidotus crocophyllus, also has a scurfy cap but the gills are orange, especially when young

 

Other Oyster-like Mushrooms

Veiled Panus (Tectella patellaris syn. Panellus patellaria)

Notes: 

Habitat & Ecology: saprophytic; on logs and branches; deciduous wood, especially alder, beech, birch, and willow; summer and fall

Cap: small upside-down cups; convex; surface fibrous; margin incurved; brown; dry or tacky; remnants of a thick, papery partial veil covering the gills

Gills: emerging from stubby stem; distant; brown

Stem: stubby and off-center, often laterally attached like an oyster

Flesh: leathery

Spore print: white 

Look-a-likes: No other gilled species have a veil and virtually no stem.

Winter Oysterling (Panellus ringens syn. Scytinotus ringens)

Notes: There is not much information on this species in the various books and online resources I use, and there are not very many observations of this species on iNaturalist. Maybe it’s a rare species here? Or maybe it is just usually overlooked?

Habitat & Ecology: saprophytic; in groups on deciduous wood, especially birch

Cap: small, oyster-like caps; cream color tinged with purple-pink; no stem

Gills: lateral attachment; pinkish 

Spore print: light-colored

Look-a-likes: Luminescent Panellus (Panellus stipticus) is also a small pinkish oyster-like mushroom but is very common, more tan-colored, has a dusting of “flour” on the surface, and can be much larger.

 

Luminescent Panellus or Bitter Oysterling (Panellus stipticus)

Notes: The name refers to its ability to glow in the dark! While the glow is more prominent in species like the Jack o’ Lantern Mushroom (Omphalotus illudens), if your eyes have adjusted to the dark (~20 min), you should be able to see the green tint. If you come across it, pick some and keep it attached to the wood so it doesn’t dry out too quickly, and wake up to check for the glowing in the middle of the night when your eyes are adjusted to darkness. The bioluminescence is thought to attract invertebrates that will disperse spores, but we don’t know the full story.

Habitat & Ecology: saprophytic; clustered on deciduous logs, stumps, and branches; summer, fall, and in mild winter time

Cap: kidney-shaped or semicircular brackets that curve to look like half of a donut; surface often has a dusting of “flour”; margin ranges from incurved and round to flared out and a bit frayed, especially in larger specimens; cap ranges from pink to tan; dry

Gills: close; coloring same as cap; cross veins present

Stem: very short and fuzzy

Flesh: white or brown, tough

Spore print: white

Look-a-likes: Crepidotus species don’t form the donut shape, have brown spore prints, are generally larger and don’t cluster as closely; Winter Oysterling (Panellus ringens) is wine-colored and seems to have thinner tissue.

 

Late Fall Oyster (Sarcomyxa serotinus syn. Panellus serotinus)

Notes: This “oyster” is not related to the edible and often cultivated Pleurotus species. It is said to be a “choice edible” which means it is edible but is not particularly tasty (this one is said to be bitter). 

Habitat & Ecology: saprophytic; on downed deciduous or coniferous wood, Hemlock usually; late fall to winter

Cap: nubby and fan-shaped; smooth surface; inrolled margin; dark green, olive, and/or yellow; viscid when wet

Gills: broadly attached to decurrent; close; yellow or white 

Stem: laterally attached; very short, tapering to the wood; same color as cap; smooth; dry

Flesh: white and tough; smell not distinctive

Spore print: yellow

Look-a-likes: 

 

Woolly Oyster (Hohenbuehelia mastrucata)

Notes: rare species

Habitat & Ecology: saprophytic; deciduous wood; summer and fall

Cap: convex to plane; surface is covered in gelatinous spikes; margin is incurved; dark grey, bluish; no stem; moist 

Gills: close to subdistant; pale grey 

Flesh: grey and rubbery; smell might be mealy

Spore print: white

Look-a-likes: Splitgill Mushroom (Schizophyllum commune) is also grey and “fuzzy” but has unique gills that look split with hairs between them while the Woolly Oyster gills are typical; other Hohenbuehelia species are smoother, or hairy and without gelatinous spikes.

 

Bear Sawgill or Bear Lentinus (Lentinellus ursinus)

Notes: 

Habitat & Ecology: saprophytic; on deciduous wood; summer and fall

Cap: semicircular shelves with lobes; margin incurved; coloring is dark brown close to the base and pale at the margin; surface densely hairy on the darker region and sometimes with a layer of “frost”; no stem; dry 

Gills: close; serrated edges, hence “sawgill”; cream-colored

Flesh: pale; smell might be spicy

Spore print: white

Look-a-likes: Crepidotus species do not have sawgills and a brown spore print; Oyster Mushrooms (Pleurotus ostreatus) have smooth caps and decurrent gills; Fox Lentinus (Lentinellus vulpinus) have light-colored hoariness, not dark, stiff hairs.

 

Stinking Orange Oyster or Mock Oyster (Phyllotopsis nidulans)

Notes: 

Habitat & Ecology: saprophytic; deciduous and coniferous wood, often newly dead with bark still attached; fall to spring

Cap: convex, semicircular cap often wavy or with lobes; surface covered in fuzzy white hairs; margin incurved; evenly light orange, paler with age; dry

Gills: laterally attached; close; orange (darker than the cap); indistinct, fuzzy base which almost looks resupinate (spreading substrate from which the cap emerges) 

Flesh: orange and soft; foul smell, like skunk cabbage or rubber

Spore print: pale pink

Look-a-likes: Saffron Crep (Crepidotus crocophyllus) has fine brown scurfiness, no delicate fuzz nor an evenly orange cap.

 

Eastern American Jack O’Lantern (Omphalotus illudens)

Notes: This mushroom is known for being a poisonous look-a-like for oysters and chanterelles, and for glowing in the dark! The bioluminescence is thought to attract invertebrates that will disperse spores, but we don’t know the full story.

Habitat & Ecology: saprophytic; clusters on deciduous stumps or buried wood, especially oak; late summer to fall

Cap: convex to plane, circular cap with a central depression or knob; surface smooth to fibrous; margin incurved or wavy with age, and sometimes dry or browning at the edge; bright orange like a pumpkin; dry, maybe greasy

Gills: decurrent (running down the stem); crowded; bright orange 

Stem: long stems taper to the base; also orange but often with a paler fibrous texture

Flesh: orange; smell not distinctive

Spore print: white to pale yellow

Look-a-likes: Growth form is similar to clustering Honey Mushrooms (Armillaria spp) which are sometimes bright yellow but not orange; Golden Oysters (Pleurotus citrinopileatus) also grow in clusters on wood but have white flesh and are bright to pale yellow with white gills.

 

Wrinkled Peach (Rhodotus palmatus)

Notes: rare, considered Near Threatened globally, mostly due to declines in host species such as Elm and Ash

Habitat & Ecology: saprophytic; wet and well-decayed hardwood in streambeds and lowlands; late spring to fall

Cap: convex to flat; surface usually covered in raised, reticulating veins, but they might be inconspicuous or absent; margin incurved; coloring ranges from brick red to pale pink; gelatinous and viscid 

Gills: narrowly attached; close; lots of shorter gills present; pink 

Stem: thick and often curved; white; surface is fibrous with exuding droplets of amber liquid; discolors dark when rubbed; dry

Flesh: rubbery, white flesh, cap is gelatinous; smell is fruity or minty or not distinctive

Spore print: pink

Look-a-likes: none!