Tricholoma argyraceum

What You Should Know

Tricholoma argyraceum is a gray-capped mushroom of the large genus Tricholoma. It is generally associated with hardwoods and may be very difficult to separate from Tricholoma scalpturatum and Tricholoma inocybeoides, both of which are nearly identical to the naked eye.

Tricholoma argyraceum is technically edible but of poor quality and inferior to other gray-capped Tricholomas. It has also been classified as inedible.

This mushroom occurs across Europe but is uncommon overall. The fruit bodies appear from June to December (occasionally earlier in Spring). The species has an ectomycorrhizal association with several genera – birch (Betula), Carpinus, oak (Quercus) and Tilia.

Tricholoma argyraceum Mushroom Identification

1. Ecology

   Mycorrhizal with hardwoods; growing alone, scattered, or gregariously; late spring and summer; Europe; North American distribution uncertain, but recorded from Midwestern and eastern hardwood forests and cottonwood river bottoms in western mountains.

2. Cap

   2.5–6.5 cm across; at first convex with a central bump, becoming broadly convex to broadly bell-shaped; dry; finely radially appressed-fibrillose, becoming finely scaly in places; brownish gray to grayish brown; margin finely woolly; when young with a whitish cortina between the margin and the stem.

3. Gills

   Attached to the stem by a notch; close; short-gills frequent; white; sometimes staining or discoloring yellow with age, especially toward the cap margin; in very young specimens often covered by a whitish cortina.

4. Stem

   2–4 cm long; 0.5–1.5 cm thick; equal, or slightly tapered to the base; bald or finely silky; often with a faint ring zone; dry; white.

5. Flesh

   White; unchanging when sliced.

6. Odor and Taste

   Mealy.

7. Chemical Reactions

   KOH negative on cap surface.

8. Spore Print

   White.

9. Microscopic Features

   Spores 3–5 x 2–2.5 µm; elongated-ellipsoid to subcylindric, with a small apiculus; smooth; hyaline in KOH; inamyloid. Lamellar trama parallel. Basidia 4-sterigmate. Cystidia not found. Pileipellis a cutis; elements 4–8 µm wide, smooth, hyaline to yellowish in KOH. Clamp connections not found.

Tricholoma argyraceum Taxonomy

French mycologist Pierre Bulliard described this species as Agaricus argyraceus in 1779, before his countryman Claude Casimir Gillet gave it its current name in 1874. The generic name derives from the Greek trichos/τριχος 'hair' and loma/λωμα 'hem', 'fringe' or 'border'. It lies within the section Terrea within the subgenus Tricholoma within the genus Tricholoma.

Tricholoma argyraceum Synonyms

1. Agaricus argyraceus Bull. 1779

2. Agaricus myomyces var. argyraceus (Bull.) Pers. 1801

3. Tricholoma argyraceum f. inocybeoides (A. Pearson) Mort. Chr. & Noordel. 1999

4. Tricholoma argyraceum var. inocybeoides (A. Pearson) Krieglst. 1991

5. Tricholoma inocybeoides A. Pearson 1938

6. Tricholoma myomyces var. argyraceum (Bull.) J.E. Lange 1933

7. Tricholoma scalpturatum var. argyraceum (Bull.) Kühner & Romagn. 1953

8. Tricholoma terreum var. argyraceum (Bull.) P. Kumm. 1871

Sources:

Photo 1 - Author: Eva Skific (Evica) (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 2 - Author: Eva Skific (Evica) (Creative Commons Attribution-Share Alike 3.0 Unported)

Photo 3 - Author: Eva Skific (Evica) (Creative Commons Attribution-Share Alike 3.0 Unported)