Fomitopsis betulina (Bull.) B.K.Cui

M.L.Han & Y.C.Dai

Piptoporus betulinus (Bull.) P. Karst.

Agarico-pulpa pseudoagaricon Paulet

Boletus suberosus L.

Boletus betulinus Bull.

Polyporus betulinus (Bull.) Fr.

Ungulina betulina (Bull.) Pat.

Fomitopsis betulina

Birch polypore, razor strop

About plant names...

The birch polypore is native to temperate regions world­wide. Its habitat is birch trees, especially white birch. They are tougher than they look: barbers once sharpened their razors on leathery strips cut from these mushrooms.

Fruits: These bracket fungi extend from the sides of dead or dying birches. (This is kind of amazing, since the bark of white birches is so durable that an entire downed tree rots before the bark degrades.) The fruits are whitish or gray-brown on top and cream-colored below, and kidney-shaped. As they mature, they become flatter and browner on top, and tan beneath. Undersides are dense clusters of pores ¹/₃₂-⅛" (1.5-5 mm) deep. The fruits have a strong pleasant mushroomy odor.

Spores: Spores are cylindrical to ellipsoidal, smooth, and 3-6 µm × 1.3-2 µm. Spore prints are white.

Edibility: Tough and bitter, these are technically edible but not desirable.

Medical: The antibiotic piptamine is obtained from this fun­gus. Piptamine shows antimicrobial activity against some Gram positive bacteria, yeasts (Candida albicans) and fungi.

Online References:

Fomitopsis betulina on Michael Kuo's MushroomExpert.com

Fomitopsis betulina on www.first-nature.com

Fomitopsis betulina on www.ediblewildfood.com

Fomitopsis betulina on Wikipedia

Fomitopsis betulina on link.springer.com

On gray birch. · 4/14/2013 · Bemis Rd, Pepperell, MA
≈ 5 × 3½" (13 × 9.2 cm)

On gray birch. · 4/14/2013 · Bemis Rd, Pepperell, MA
≈ 5 × 3½" (13 × 9.2 cm)

On gray birch. · 4/14/2013 · Bemis Rd, Pepperell, MA
≈ 4½ × 3" (11 × 7.9 cm)

10/2/2020 · Gordon and Kathy’s, Prospect, ME

Fomitopsis betulina description by Thomas H. Kent, last updated 25 May 2020.

© FloraFinder.org. All rights reserved.

9/27/2013 · Gordon and Kathy’s, Prospect, ME
≈ 7 × 5" (18 × 13 cm)

1/7/2012 · Beaver Brook Association Trails, Hollis, NH
≈ 7 × 4½" (17 × 11 cm)

12/9/2011 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 9 × 6" (22 × 14 cm)

1/7/2012 · Beaver Brook Association Trails, Hollis, NH
≈ 5 × 3½" (13 × 9.2 cm)

1/7/2012 · Beaver Brook Association Trails, Hollis, NH
≈ 14 × 21" (34 × 52 cm)

3/21/2012 · Nashua River Rail Trail, Groton Center, Groton, MA
≈ 5 × 5" (13 × 12 cm)

9/27/2013 · Gordon and Kathy’s, Prospect, ME
≈ 9 × 6" (22 × 15 cm)

1/7/2012 · Beaver Brook Association Trails, Hollis, NH
≈ 8 × 5" (19 × 13 cm)