Because I can…I have local oak galls, acorns and walnuts (imported from the wilds of West Chester, PA) to choose from to use for tannins for cotton dye prep. Here they are in their form of waiting in the wings till needed.
Oak Galls collected here in Blanco county 
Walnuts in their slimy & stinky form after a year soaking with the newer walnuts carried here by Marge from West Chester, Pa.
And the ancient acorns from about two years ago…..whose mold I will not inflict upon anyone but myself!
Testing between the walnut and the oak galls I get a dark tone & a yellow tone.
The walnut pushes brown…duh 
And the oak galls push yellow red.
Oak galls are the recommendation by several authors. I will use them in conjuction with alum acetate and a chalk dunging. I believe with dilution the cotton will shift to a beige color.
Since different skeins will be overdyed with madder, persimmon and indigo I am not concerned about the mordant undertone. The tannin’s impact will be minimal on the final colors. The goal is to get the tannin in play on the fibers so they play nice with the alum acetate, the dunging and the final dye baths.
debmcclintock 