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 
I have a big bucket of galls I’ve collected this fall. Can you provide directions / recipe for how to create the mordent from these? Should I crack them open first (it looks like yours are whole)? Is there a recommended ratio of water to galls? Or should I just cover them with water? Should I stir them regularly or just ignore them? What’s the minimum amount of time I should let them ferment?
Do you use the same approach for acorns?
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Deb, the tannin is used in conjunction with alum acetate and calcium carbonate. Now, I just soak my until they are softened and smash them. You are leaching the tannin out of them. If you look around at acorn prep for acorn flour you’ll see that tannin is leached out of the acorns. We dyers WANT the tannin, hence we keep the water. I ignore my soaking oak galls. I put them in jars, fill it with water and leave them alone. I do go back and loosen the lids while the goods are fermenting to release air. Low maintenance…..is my motto. I have some acorns and oak galls soaking in jars that are two year vintages. I do note how many grams are in each jar so I know how much raw material I am using. Once again it depends. I put enough for what I have on hand for a light color that will be overdid. Maiwa has generously posted recipes. Check them out here http://maiwahandprints.blogspot.com/2013/01/natural-dyes-mordants-part-3.html Good luck with your experimenting. You’ll get different colors from the acorns and the oak galls. Search my blog for the tannins and you’ll see some wools that show the subtle differences. These colors make great neutrals.
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Thanks for such an extensive reply – great link to Maiwah – I like your low key approach and really love your blog!
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Is there any residue perfume? 🙂 Looks a potent brew.
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Hey Kay, Actually the acorns smell like a whiskey mash, the walnuts a little less romantic. The worst is fermenting persimmons. They reek. I always pick a day when it is windy and ensure I have old clothes and shoes on. When I process the juice the residual smell is, as you say, potent….
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I dye with walnuts. (have tree in backyard) This year I tried using them whole and just bunged them in a crockpot with water and added goods to dye (raw wool or cotton cloth) and let it simmer away. Always turned off the crockpot in the evening and resumed dyeing in the morning. Some stuff was dyed for days, some hours. Just kept adding water as needed. Discovered that smashed walnuts (which is what I had used previously) gave off a darker color but then I was picking bits out when it was time to comb the fiber. I dye outside and you do have to keep an eye on the process. Had a determined squirrel rip the lid up on my crockpot while dyeing with one batch of walnuts . The heat did not deter him in the least. Saw him sitting 5 feet from my back door trying desperately to get to the delicious aroma within the pot. Chicago squirrels are not noted for intelligence.
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Walnut *as* a tannin? Are you using a weaker solution? I just ask because i thought walnut was substantive and might block other dyes? I haven’t access to other tannins, but have a great whack of frozen and dried walnuts.
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Try a weak concentrate of walnut. If too much will affect your other color….
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thank you—i guess i’ll keep the “failed” baths then 😉
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