Birch Polypore
ExploreFungi
Birch Polypore
fomitopsis betulina
The Birch Polypore is an incredibly common bracket fungus that acts as a quiet sentinel of northern forests. Growing almost exclusively on birch trees, this pale, cushion-shaped mushroom begins its life as a parasite, slowly weakening its host, before transitioning into a saprobe that decomposes the dead wood. For thousands of years, humans have held a deep relationship with this fungus, utilizing its versatile corky flesh for medicine, bandage-making, and even tool sharpening. Whether you are a bushcraft enthusiast or a casual hiker, encountering this silent forest dweller is a testament to the complex, cyclical processes of forest decay and rebirth.
Habitat: Found growing almost exclusively on living, dying, or dead birch trees in temperate and boreal forests.
Appearance
Characterized by its smooth, hoof-shaped or kidney-shaped bracket, the Birch Polypore lacks a distinct stem and fuses directly to birch bark. Its upper surface is initially white to pale cream, turning a dull greyish-brown as it matures, and features a rounded, incurved edge. The underside consists of a flat, white pore surface that bruises slightly yellow or brown when scratched. Individual brackets typically range from 5 to 25 centimeters in width and have a tough, rubbery texture when fresh, which dries to a corky consistency.
KingdomFungiPhylumBasidiomycotaClassAgaricomycetesOrderPolyporalesFamilyFomitopsidaceaeGenusFomitopsis
Category
FungiRarity
Common
Danger
1/5 · Very low
Snaps
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Interesting facts
A piece of birch polypore was found in the gear of Ötzi the Iceman, a 5,300-year-old mummy, likely carried for its medicinal properties.
Because its velvety, corky interior smolders very slowly without catching fire, it was historically used to transport embers from campfire to campfire.
Historically, barbers used dried strips of this fungus to sharpen their razors, giving it the common nickname of razor strop fungus.
Special abilities
Ability
Selective Wood Decay
Produces specialized enzymes that selectively break down the cellulose and hemicellulose in birch wood, causing a rapid brown rot that returns nutrients to the soil.
Ability
Natural Plaster Creation
The inner flesh can be peeled into sterile, flexible strips that naturally stop bleeding, act as antiseptic bandages, and assist in wound healing.
Ability
Chemical Defense Shield
Synthesizes bioactive molecules like piptamine, which protect the fruiting body from bacterial infections and competing fungal species.
Measurements & details
- Length
- 5-25 cm
- Weight
- 0.1-1.5 kg
- Lifespan
- 1 years
Diet & Feeding
As a parasitic and saprophytic organism, it absorbs nutrients directly from birch wood by secreting powerful wood-decaying enzymes.
Age differences: Begins as a parasite feeding on living birch tissues, then transitions to a saprobe feeding on dead wood after the tree dies.
Primary Foods
- Birch cellulose
- Birch hemicellulose
- Lignified wood cells
Foraging Method
- Absorption
Ecological connections
host plant
Silver Birch
Betula pendula
Serves as the host tree where the fungus establishes its mycelium and produces its fruiting brackets.
eaten by
Cis beetle
Cis bilamellatus
The larvae of this tiny beetle tunnel into and feed upon the corky bracket of the fungus.
parasite
Polypore parasite
Hypocrea pulvinata
A specialized mycoparasitic fungus that grows as a yellow cushion over the old pores of the birch polypore.
Traits
No trait badges are assigned for this object yet.
Also known as
No aliases listed yet.
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Safety
Danger
1/5 · Very low
No special safety notes yet.
Frequently Asked Questions
How long is Birch Polypore?
5-25 cm
How much does Birch Polypore weigh?
0.1-1.5 kg
How long does Birch Polypore live?
1 years
What does Birch Polypore eat?
As a parasitic and saprophytic organism, it absorbs nutrients directly from birch wood by secreting powerful wood-decaying enzymes.
Where is Birch Polypore usually found?
Found growing almost exclusively on living, dying, or dead birch trees in temperate and boreal forests.
How does Birch Polypore hunt?
Absorption
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Recent Snaps
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Where to spot
Zoo30 sightings12 species
New York, US
Binghamton Zoo at Ross Park
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Park30 sightings12 species
Massachusetts, US
Fells Connector Parkways
You might spot Striped Wintergreen, Mapleleaf Viburnum, and Duck.
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Park30 sightings12 species
Pennsylvania, US
Joseph E. Ibberson Conservation Area
You might spot Downy Rattlesnake Plantain and Striped Wintergreen.
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