Well here is an example of Black Walnut bark.
Perfect and on a much smaller tree obviously, but I think you took a great picture with a Black Walnut and a Black Walnut PD... the pinnate shape of leaf structure gives it another point toward BW.
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Yes, I can see that you took care of it, Madcap.. Makes me wonder at the modern Fender Custom stuff that looks so beat up... Nice to see your rigs.
I keep the scalp, (headstock) of my first home-made bass as a center piece decoration on my wall rack for guitars (4) .