Originally Posted by
len mccoy
...During my limited time on Okinawa I saw and practiced a lot of makiwara but I never saw anyone using herbal preparations...
I think you answered your own question. I also just asked my brother, who trained briefly under Hohan Soken and Fusei Kisei, and he, too, doesn't recall seeing anything applied before makiwara sessions. He said he does recall Fusei Kisei using a bucket full of rice or buckwheat for spear-hand training, but is pretty sure nothing was added to it.
Yours in Budo,
---Brian---