Fresh growth from June to September

Birch polypore

Fomitopsis betulina

Inedible

A pale, smooth annual bracket attached directly to birch, with fine white to cream pores and one short layer of tubes in section.

Guide contents

Season

Fresh annual growth begins in June and develops mainly in August and September. Old brackets can remain visible beyond autumn.

Directly on trunks and branches of weakened, dying or dead birches, where the species causes brown rot in the wood.

Check several visible features before retaining a species name.

Reviewed scientific notes are shown in French.

Pale, thick bracket without zones
The annual bracket is kidney-shaped or rounded like a hoof, white to beige, with a smooth upper surface without marked concentric zones and a thick, downturned margin.
Fine white to cream pores
The underside has small, round to angular pores, about three to five per millimetre, without gills, folds or spines.
Birch attachment and white section
The bracket attaches directly to the wood without a central stem. A section shows thick white flesh above one short, detachable layer of tubes.

First identify the supporting tree as birch and trace the bracket to where it attaches directly to the wood.
Check the pale, unzoned upper surface, thick margin and finely pored underside together.
Make a local section to confirm the white flesh and one short layer of tubes.

Reviewed scientific notes are shown in French.

Fomes fomentarius: Fomes forme un sabot gris zoné, dur et pérenne avec chair brune et couches de tubes; F. betulina est annuel, plus lisse brun pâle, à chair blanche.
Fomitopsis pinicola: F. pinicola est pérenne et montre généralement des zones sombres et un bourrelet rouge orangé; F. betulina est annuel brun pâle à chair blanche, sur bouleau.