Posted: 10/09/2017 at 19:09
Comfrey roots are thick, dark brown (white inside) quite brittle and go down a long way (several feet) so I think you have something else there. As nut says, a photo would be really useful.
Edit: You posted the photo while I was typing!
Those look very much like Jerusalem artichoke tubers to me, or possibly something else in the sunflower family.
Last edited: 10 September 2017 19:12:05