Fungus · GBIF taxon 9113338
Elm Mushroom
Hypsizygus ulmariusAlso known as Elm Oyster Mushroom, Elm Leech
Elm mushrooms fruit high on the trunks and knot-holes of mature deciduous trees, emerging singly or in small clusters during cool autumn weather. They cause a slow heart-rot inside aging hardwoods, breaking down lignin while sustaining cavity space critical for nesting birds and small mammals. Although superficially resembling wood-decay oysters, their stout central or off-center stems and adnate gill attachment clearly distinguish them upon closer inspection.
Wood-DecayAutumn-FruitingForest Fungus
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Saprophytic and weak parasite (breaks down hardwood cellulose and lignin)
Predators
- Fungus Gnat Larvae
- Slugs
- Eastern Gray Squirrel
ThreatsRemoval of mature host trees, forest fragmentation, and urban arboricultural pruning
HabitatsDeciduous woodlands, river valleys, and urban parks with mature hardwood trees
Life spanFruiting body lasts 1–3 weeks; mycelium persists for decades within host wood
Size / weightNot available
Classification
- OrderAgaricales
- FamilyLyophyllaceae
- GenusHypsizygus
- SpeciesHypsizygus ulmarius
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Many edible mushrooms have toxic look-alikes; never eat wild fungi based on app identification alone.
Responsible observation
- Look Upward: Scan the high wounds and branch scars of older elm and boxelder trees where fruit bodies typically sprout.
- Examine Gill Attachment: Check that the gills terminate cleanly near the stem rather than running deeply down it to rule out Pleurotus species.
- Leave in Place: Allow aging specimens to disperse their white spores and provide shelter for forest microfauna.
Look-alike voir ci-dessous / see below / CC BY 3.0 · cc-by
Host Plant no rights reserved, uploaded by Étienne Lacroix-Carignan · cc0
Host Plant CK Kelly / CC BY 4.0 · cc-by
Close Relative Akira.Sasaki / Public domain · cc0
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