Jumping in.here. I harvest mullein for the root, as well as the leaves and flowers. My current monster mullein is over 8' tall! See attached photo.
I use the root to make an ointment for lower back pain. It is extremely hard, even when pulled in the spring of the 2nd year.
A heavy, sharp and thick knife can force-split the thick pieces of the root apart. I have some root that are simply to hard to split by hand.
I'm looking for a permit with a good grinder - not a Ninja-type! - to run a small quantity of root through. I will pay for shipping both ways and gift you with our Arnica & Calendula ointment [comfrey (leaf), arnica (flower), calendula (flower)] for about 5 minutes of grinding. Don't need powder, just a grind into smaller pieces.
I've got root now to grind. Message me if interested. See www.catskillsComfrey.com. fwiw, I'm in upstate NY.
Spirits.
Seth J Hersh