KPFA's The Herbal Highway has an interview of Rebecca Burgess posted on the radio station's website at www.kpfa.org/archive/id/87046. The show originally aired on December 13, 2012.
The interview runs almost an hour. I spun more Perendale wool into yarn while listening.
I appreciated Burgess' point about the comparatively complex colour that comes from the multiple pigments in natural dyes.
I was also interested to hear about the study done on the alleviating effect of turmeric-dyed cloth on rheumatoid arthritis pain. I recently read most of Jenny Dean's Wild Color and wrote turmeric off for some reason after reading Dean's description, probably colour-fastness. Now turmeric interests me again. Nice to think that cloth could be therapeutic in contact with skin. I regularly cook turmeric and rice because ingestion of the spice is supposed to be good for health. I wonder whether turmeric in cloth counteracts inflammation or just reduces pain. In the study people slept on turmeric-dyed bedclothes. Would be hard to fit a sheet into a dye pot of the size commonly used by dyers at home.