Some of the plants you can use for natural dyeing.

The Western Red Cedar - Thuja plicata, is British Columbia's provincial tree. It grows to heights of over 50 metres tall. The bark is grey to reddish brown and has an aromatic wood, with glossy yellow/green leaves.

Most tree barks will produce some type of dye, due to the tannins that are in the bark. To extract the dye does take some time as the bark needs to soak in water for a day or two, prior to dyeing.

I am fortunate to have several large red cedar trees on our property. I pulled a few strips of bark from each tree and chopped them into small pieces. I soaked the bark chips in water overnight. If you don't have red cedars growing in your back yard, try obtaining some cedar bark mulch (that hasn't been leached) from a gardening shop.

The following day I filled a dyepot with hot water and put the bark mixture into the dyepot. I let the dye mixture simmer for a few hours on low heat.

Then I put clean fleece that had been processed in an Alum mordant, into the dyepot. I let the mixture simmer for about 2-3 hours, on low heat. The wool only had a hint of colour in it. So I then let it simmer for another few hours. It was a bit darker by then. I turned off the heat, and left the mixture to sit overnight in the dyepot.

The next morning, the wool had dyed to a pleasing, soft shade of honey.

Pictures
Some more pictures of my dye project.

Ecological Impact of Cedar
The Western Red Cedar acts as an anchor for other trees and plants, securing them in the soil and providing shade and a wind break. They provide shelter for birds and smaller animals throughout the year, protecting them against rain and snow.

Natural History
Local First Nations people called the Red Cedar the "Tree of Life" because it was used for making baskets and clothing, ropes, fish traps, canoes and other articles.

Western Red Cedar Fact Sheet
This page has a good description of how to identify this tree, along with closeup photos.