Plants to Dye For

photo from eHow-sumac

I'm going to try and utilize more of the plants that are growing around here for dying my fiber.  I've tried beets before and onion skins, but I'm going to do some experimenting.  We have a lot of plants that are dye plants.
These are the colors using alum as a mordant and dying wool.

For yellow dyes-
yellow yarrow
goldenrod
tansy
black-eyed susan
sunflowers
dandelion
dock

Blue dye
Woad-I guess it grows wild around here, I'm going to go out foraging and see what I can find.
blueberries

Brown dye
Red Sumac berries
tea

Apricot-Orange dye
jewelweed
carrots

green-
lamb's quarters
carrot tops
spinach
queen anne's lace

There are more, but most fall under the yellow/gold dye catagory.  These are just some of the things that I have in the field, gardens, or woods that can be used as dyestuffs. 
If you want to know if a plant has color, place it on a newspaper, put a piece of muslin over it and pound it with a hammer.  If the juice of the plant leaves color, you can give it a try.  I'm going to try huckleberries.  I'm hoping to get a nice purple hue.  I wonder if you could get a pink from rasberries??

So much to try, so little time.