I finally have a local source for walnut hulls, and I processed a batch over the last two days. I had about two quarts of hulls, green and brown (plus a walnut or two) ~ and with two extractions I now have nearly two gallons of gorgeous inky sepia colored dye. I couldn't resist sticking a couple pieces of bound fabric into the extraction pot.
I haven't used walnuts before. It's pretty amazing how much color you get from them, also how far a small amount will go. I could have done several more extractions and still gotten gallons more dye...but I'm out of gallon jars and can always get more hulls when I need them. FYI if you've been looking for an eco dye that will dye nylon, walnut is it. I had another piece of fabric scrunched up in nylon mesh in the pot, and that nylon is permanently a very dark brown!
I have a big eco dyed piece waiting to be unbundled. It's a cotton button down shirt that I processed last Thursday. It's been sitting outside since Friday morning. Sometime this week I'll unwrap it. I'm planning to wear it to a community Thanksgiving supper next Saturday.