you just want to add some acid (enough to cover the bark, but not too much to require an unnecessarily high about of base), and cook it into the material (you can toss it in the oven, or on the stove).
you really just want to lyse the cells (rupture the cell walls), allowing the goodies contained within to flow out.
after that you add enough extra base to negate any prior acidity, and carry on as normal.
My wind instrument is the bong
CHANGA IN THE BONGA!
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