Locating the Fungus
Most of the time we go out of our way to avoid a fungus, but you should go out of your way to get chaga. First, identify where birch trees grow plentifully near you, preferably in a mountainous area. Scout for black-colored growths on the otherwise light colored bark. When you find some likely candidates (often at the site of forked branches and tree injuries) knock off a hunk with a rock or hatchet. Inspect the inner material to check for the punk-wood center and also take a look at the color. This fungus should be yellowish, orange, or rusty brown in color. Finally, scrape off a bit of dust and see how easily it ignites with a spark. Birch tinder fungus should light easily and burn well if it is dry and not rotten.