Estimated value
$8–20/lb fresh
Dried $20–60/lb
Only from living birch, cracked black exterior, rust-gold interior. Fake 'chaga' on other trees is common.
medicinal · medicinal
Chaga
Inonotus obliquus
Also called Clinker polypore, Birch conk
Field marks
- Spore print
- n/a (sterile conk)
- Smell
- Vanilla, earth, tea
- Trees / hosts
- Paper birch, Yellow birch, Silver birch
- Elevation
- Boreal lowlands to hills.
Description
Burned-looking black clinker on living birch. Inside is rust-orange and corky. It is a sterile conk, not a classic mushroom. Overharvest is a real conservation issue.
Where it grows
Living birch in boreal and mixed forest.
How to find it
Walk birch stands in winter when the black clinker pops against snow. Confirm living tree + gold interior.
How to pick
Take a portion, never girdle the tree. A hatchet, not a truck winch. If the tree is dead, skip — quality and ethics drop.
Medicinal notes
Traditional Siberian and First Nations tea. Antioxidant-rich (melanin, betulin derivatives from the birch). Human clinical evidence is limited. Not a cancer treatment. Consult a clinician.
Psychoactive / controlled
None.
Law
Legal as tea. Some jurisdictions and Indigenous territories restrict commercial harvest. Sustainability first.
Lookalikes
Black knot / burls / burned wood
No rust-gold cork interior. Worthless and sometimes moldy.
Field ID ticket
Tick every required mark in the woods. 0/3 required. This still is not laboratory certainty.
Do not eat or sell this specimen. Missing required marks.