(Hypsizygus ulmarius)
Conservation • Description • Habitat • Ecology • Distribution • Taxonomy
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Description |
Elm oyster is a large mushroom. It is widespread but not common in eastern United States. It usually occurs singlyn or in a small cluster. It is found from August to December growing from a branch scar or other wound high in a living hardwood tree, especially elm and box elder. The cap is 2″ to 6″ in diameter. When young, the cap is convex and the margin is rolled under. The upper surface is white and smooth. As it ages it flattens out and the center becomes slightly sunken. The upper surface turns creamy buff or tan and develops cracks, forming a pattern of small scales or patches. The stalk is stout, 2″ to 4″ long, and ⅜″ to 1″ thick. It is whitish, solid, fibrous, smooth, dry, and usually hairless, sometimes finely hairy. It is attached centrally or slightly off center, and is sometimes enlarged at the base. There is no cup-like covering (volva) at the base of the stalk, and there are no remnants of a universal veil clinging to the stalk. The flesh is firm and white. It is edible but tough. The gills are closely spaced and whitish at first, becoming cream-colored with age. They are attached to the stalk but do not run down the stalk. The spore print is white to buff. |
Similar Species |
Brown Beech Mushroom (Hypsizygus tessellatus) is virtually identical in size and appearance. Fresh specimens often have a pattern of round watery spots on the cap. It grows on aspens, cottonwoods, and sugar maple, and it usually occurs in dense clusters. |
Habitat and Hosts |
Hardwoods, especially elm and box elder |
Ecology |
Season |
August to December |
Distribution |
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Sources |
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10/3/2024 | ||
Occurrence |
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Taxonomy |
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Kingdom |
Fungi (fungi) |
Subkingdom |
Dikarya |
Phylum |
Basidiomycota (club fungi) |
Subphylum |
Agaricomycotina (jelly fungi, yeasts, and mushrooms) |
Class |
Agaricomycetes (mushrooms, bracket fungi, puffballs, and allies) |
Subclass |
Agaricomycetidae |
Order |
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Suborder |
Tricholomatineae |
Family |
Lyophyllaceae |
Genus |
Hypsizygus |
Subordinate Taxa |
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Synonyms |
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Agaricus ulmarius Dendrosarcus ulmarius Lyophyllum ulmarium Micromphale ulmarium Pleuropus ulmarius |
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Common Names |
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Elm Mushroom Elm Oyster |
Glossary
Universal veil
An egg-like structure that envelopes all or most of a developing gill mushroom. Remnants of the universal veil sometimes visible on a mature mushroom are patchy warts on the cap, a ring on the stalk, and a volva at the base of the stalk.
Volva
Also called cup. A cup-like covering at the base of a mushroom stem, sometimes buried. It is the remnants of the universal veil ruptured by the mushroom pushing through. It is found on Amanita, Volvariella, and some other mushrooms.
Visitor Photos |
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Amy Stifter |
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Lynda Meyers |
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Miranda Sieh |
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I have been enjoying the photos and info on your website. I have been learning about wild mushrooms and growing cultivated mushrooms for the last few years with an experienced mentor. |
Today (Oct 3) I found 2 mushrooms that I think are elm oysters growing on a living box elder on my farm in East central MN. The feature that gives me pause is the texture of the stipe. It is not smooth but almost scaly or shaggy. I can not find an elm oyster look alike with a shaggy stipe. The weather has been humid, but we are in need of rain. Any advice would be appreciated. |
Wags |
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Mark Volesky |
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Found four in western Becker County. All attached to three maple trees. |
Kirk Nelson |
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Growing on a boxelder |
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Jessica Marquez |
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Cluster of elm oyster mushrooms growing surprisingly low (4’) off the ground on a box elder tree near Silver Creek in Quarry Hill; found Dec. 20th, 2019. |
(They are a frequent sight here as well as along the Douglas Trail starting in late August, but this is as late in the year as I’ve found them so intact!). |
Jeff |
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MinnesotaSeasons.com Photos |
Slideshows |
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Visitor Videos |
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Other Videos |
Elm Mushroom (Hypsizygus ulmarius) on Tree |
About
Published on Sep 20, 2010 Photographed at the Turtle River State Park, North Dakota (12 September 2010). |
Elm Mushroom (Hypsizygus ulmarius) on Boxelder |
About
Published on Sep 20, 2010 This specimen was found growing 5 meters from the ground. Photographed at the Turtle River State Park, North Dakota (19 September 2010). Go here to learn more about this species: https://www.youtube.com/redirect?q=http%3A%2F%2Fwww.mushroomexpert.com%2Fhypsizygus_ulmarius.html&redir_token=oZnTZUyQLFWY2FAuIgLZVcAA7CV8MTUwOTI4MTM3NEAxNTA5MTk0OTc0&event=video_description&v=w3TFrMESkDY |
Elm Oyster foraging - Hypsizygus ulmarius |
About
Published on Nov 10, 2015 This is me. Unsuccessfully being able to reach the common. but illusive, Elm Oysters. |
Elm Oyster wild mushroom |
About
Published on Nov 1, 2011 Elm Oyster is a Edible wild mushroom but tough https://www.youtube.com/redirect?redir_token=yRR8iZwUoc0P_jTrCsLUJ5Z32uR8MTUwOTI4MTU3M0AxNTA5MTk1MTcz&v=9CIv19tI6aY&q=http%3A%2F%2Fwww.gabodabuilding.com%2FMoreMushrooms.html&event=video_description |
Visitor Sightings |
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Lynda Meyers 8/27/2022 |
Location: Red River at Moorhead |
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Apricity Apricity |
Location: Martin County, Fairmont, MN |
Wags 9/28/2021 |
Location: near Theodore Wirth Park in Minneapolis |
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Mark Volesky 9/17/2021 |
Location: Becker County Found four in western Becker county. All attached to three maple trees. |
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Kirk Nelson 9/20/2020 |
Location: Fort Snelling State Park |
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nltr 9/7/2019 |
Location: May Township found growing out of crotch of young elm and out of crack in young elm. Wooded acreage |
Jeff 10/14/2017 |
Location: Rush City |
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Kirk Nelson 9/10/2017 |
Location: Lebanon Hills Regional Park Growing on a boxelder |
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MinnesotaSeasons.com Sightings |
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Created: 10/28/2017 Last Updated: © MinnesotaSeasons.com. All rights reserved. |