Forage for 1 lb fireweed leaves. Collect them just below the blossom using scissors or a small knife. Do not use leaves too near the ground as they can look weepy and do not ferment as well.
Using your hands, smash leaves so they are "broken." Place in glass jar with lid. Store in humid environment for 2 days, shaking once or twice a day and quickly discarding any sign of molding leaves.
After 2 days, place leaves on a cookie sheet. Preheat oven to 350F and bake leaves for 20 minutes until they are completely dry. Let cool and store in a air-tight container for up to a year.
Brew tea to desired strength following the same method that you would for other loose tea leaves.