Jérôme
> I don't think most people know that the best figure is NOT down in the bottom roots, but rather on the top of the roots near the surface of the ground where they make a right angle turn up.

The best figures are indeed the parts where the horizontal roots meet the main vertical root (pivot).
Walnut can produce various kinds of "burl" for which we have different designations in French: "ronce de noyer", "loupe", etc.
The most expensive and sought after cut for guns blanks where the straight parts of the pivot though (family business).

Walnut is great, usable from the roots to the leaves.