Epithet = after Latin: Gallia, Gaul, a region of western Europe. Genus = diminutive of Trametes.
Polypore with sessile brackets but can be effused-reflexed.
Key characters are the large pores and the coarsely hispid cap surface, brown to gray; context is brown.
Bracket is corky or tough, up to 10 cm wide (or more) and projecting up to 7 cm. Upper surface hairs are brown, later gray.
Hairs are dense and erect (hispid to villose). May have marginal zone with shorter hairs.
Context below hairs rusty to umber brown, thin or up to 1 cm thick; darkening with KOH.
Context is lacking a black zone and has no sharp division between the context and the hairy covering.
Tubes pale, whitish to gray on inner walls, thin-walled; tube layer up to 1.5 cm thick.
Pore surface brown to gray (darker on end view); pores angular to elongated, large, 1–3 mm in diameter; in age elongated and deeply split.
Hyphal system trimitic with clamped generative hyphae, thick-walled skeletal hyphae golden brown in trama and context, and branching binding hyphae.
Skeletal hyphae cyanophilous and metachromatic.
Basidiospores cylindrical, variable in size, 10–16 × 3–5 µm.
Compare carefully with T. trogii which has pale whitish context (inside above the pores); basidiospores smaller; thinner brackets; cap is generally paler and the hairs have pale roots unlike T. gallica where the cap hairs are more evenly dark brown to gray.
Trametopsis cervina has hairs that are less coarse, coloration generally more yellow, brackets up to 21 × 5 cm.
Trametes hirsuta has hirsute surface that has weak zones of gray, sometimes yellowish; pores are smaller and turn gray; pores round and surface even, not lacerate.
Trametes villosa (southern USA) is thinner and more flexible.
Some Antrodia species can be mistaken for T. gallica but Antrodia lack the coarse hispid hairs on the cap; pores are smaller in some species.
White rot of dead hardwoods; most common apparently on Salix (willow) and Populus (cottonwood, aspen); on many native hardwoods; can also be on exotic trees in gardens and parks.
Spring to fall, overwinters.
Widespread in North America, rare in southeastern states. Also Europe, North Africa, and Asia.
Chicago Region status
Rare. The recent collection at Indiana Dunes was in oak savanna with aspen and birch also present. The Morton Grove area collection was floodplain forest so it could have been on cottonwood.
In Moffatt (1909) as Trametes peckii.
PRL 7605 from 2008 and PRL 11462 from 2013 were mistakenly identified as T. trogii. Other collections identified as T. gallica are actually T. trogii.
Taxon Details and Links
Revista Brasileira de Botânica 9 (1): 44 (1986)
≡ Basionym, Sanctioned:
Systema Mycologicum 1: 345 (1821)
Epicrisis Systematis Mycologici: 489 (1838)