Bark pigment and bark tanning
Bark of various trees can be used for making pigments as well as for tanning of leather. Bark tanning is the ancient process of creating a durable, water repellent leather by tanning animal hide with the bark from trees. The process takes several months to complete but will result in a finished leather that you can use to create attire, clothing accessories, saddles, wallets, and other leather items.
For creating colours you can think of Alder (orange) Butternut Tree (light yelllow-orange), Eucalyptus (all parts, leaves and bark: deep rust red, yellow, green, orange and chocolate brown, best for silk or wool fibers), Birch (Light brown, alum to set) Broom (yellow/brown), Grand Fir (pink) Dogwood (blue), Canadian Hemlock (reddish brown) and many more!