Wilton® Golden Yellow Icing gel on wool yarn
goldenrod (Fibershed link to "Harvesting Color"), blog here: http://www.rebeccarburgess.com/
Dyeing with pokeberries, OMG, a use for those annoying plants that pop up all over thanks to the birds, LOL
Silk Hankies dyed with Acid dyes-easy microwave instructions for acid dyes
The Merry Hooker Woolens...a great dyeing tutorial. She also explains her method of organizing her work and supplies. This could apply to dyeing yarn as well as fabric.
Good vid to watch before Dyeing roving for spinning.
Fiber dyeing with Cochineal
Marigolds for Dyeing - botanicalcolrs.com - Image courtesy of Tolt Yarn & Wool
Samples naturally dyed with mulberry
Horsetail - Equisetum Arvense