[lonlazarus]

That's also my understanding. I do wonder if that's a bit of a misunderstanding about not practicing agriculture, though. They did practice forest management with intentional burns. I'm pretty interested in traditional English forest management, and reducing brush and decreasing canopy increased the amount of forest "products" available to people, from building materials (basketry, hut materials, etc) to increased yields from under story vegetation.

It's a bit of a digression, but it's a subject I find interesting and rarely pops up in hacker news. :)