Amazing info in this article. This lady has been researching pokeberries as dye for 18 years. And she has finally got it figured out. No loss in color in Ancient fabric died w pokeberries. Pokeberry colors range from bright fushia to magenta to raspberry, and will...
The blog post at this link provides a nice description of Swaledale as well as showing what it looks like both dyed and spun. http://www.thefiberofmybeing.net/2012/02/oh-the-fiber-my-swaledale-fiber/
I am a huge fan of Grace Shalom Hopkins's videos. Here's her take on dyeing self-striping roving.