Chaga

Inonotus obliquus

Also called: Chaga, Clinker Polypore, Birch Conk, Black Mass

Overview

Chaga is not harvested for fruiting bodies — it is a perennial sterile conk present year-round on living birch. Bioactive compound concentration peaks during birch dormancy, when sap has receded to the root system after sustained freezing temperatures. The best chaga is winter chaga. Harvest only the outer black material, leaving the orange-brown interior layer and at least 20% of the conk mass to allow the organism to survive and regrow. Sustainable harvest from the same tree can be repeated every 3–5 years.

Edibility

Tea / extract only

Rarity

uncommon

Trophic mode

parasitic

Typical peak

Year-round

Season

Year-round (presence, not fruiting) — typical fruiting months: , Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov.

Host trees & substrate

Living birch (yellow, paper, black)

Where it grows

See live fruiting predictions for Chaga on the forecast home page, or browse the full field guide.

Always confirm wild-mushroom identification with multiple sources and a knowledgeable local expert before consuming. Read the foraging safety guide.