Iv found the little xxxxx there all over my wooden gate so every time I go in and out of my animal yard I get them on me. So I'm sure there wood mites. They don't seem to bother my dogs. And I don't get them on me if I handle my birds.
I only treat, with permethrin, if there are mites or lice on the birds. Haven't ever (yet!) had grain mites in feed, and I don't care what else is out there, just what's on the birds.
Mary