Most bows that I make now are with green staves. No problems with bark removal.No shellac, no paint , no glue involved ,and no stock of staves. Reduce stave enough to bend on a form ,and make all the corrections.Dry time is shortened significantly that way. They dry natural in my basement. It is what works best for me. That being said, if you can chase a ring on Osage, Black Locust, even White oak you can carefully remove 3 year old Birch bark using a draw knife ,and a scraper of your choice, and sand paper if need be.