FYI, Natures Footprint is located just off the Mt Baker Highway. But here’s the kicker, the owner gets his pumice from Oregon and brings it back to Washington mainly something to do with worms.
I used get my pumice directly from him until he ran out. He is very “flaky”, doesn’t return calls.
My new source has all the pumice I could ever dream of.
If you want the best for your trees, I have it. $50 1/2 cu ft (USPS large flat rate box) washed and dried any grain size. check out link below 
