I haven't turned much root that I am aware of, although my Vipor dug up a Hydrangea a few years back that had a well established woody root and looked very similar to what you show here.
I made a slimline from it which is now a rich yellow in colour but the wood has shrunk away from the nib and cap and is showing the brass tube at the ends.
I never realised it had that much drying to still do after the turning.