All walnuts, pecans, and filberts have similar hulls.
Yeah, walnut have fleshy hulls surrounding the nut, but the chemistry and pharmacological actions are what I am interested in. The herbalist that was weighing in on the specific actions might have some idea.
BTW, filberts (or as we call them hazelnuts) are very different critters. The husk if much more like an extension of the sepal rather than a swelling of the ovary wall. Pecans are right out of my experience and climate zone.