"Regions are 'interpenetrating bodies in semi-simultaneous spaces' (Cafard, 1989). Biota, watersheds, landforms, and elevations are just a few of the facets that define a region. Culture areas, in the same way, have subsets such as dialects, religions, sorts of arrow-release, types of tools, myth motifs, musical scales, art styles. One sort of regional outline would be floristic. The coastal Douglas Fir, as the definitive tree of the Pacific Northwest, is an example. [...] Its northern limit is around the Skeena River in British Columbia. It is found west of the crest through Washington, Oregon, and northern California. The southern coastal limit of Douglas Fir is about the same as that of salmon, which do not run south of the Big Sur River. Inland it grows down the west slope of the Sierra as far south as the north fork of the San Joaquin River. That outline describes the boundary of a larger natural region that runs across three states and one international border.

"The presence of this tree signifies a rainfall and temperature range and will indicate what your agriculture might be, how steep the pitch of your roof, what raincoats you'd need. You don't have to know such details to get by in the modern cities of Portland or Bellingham. But if you do know what is taught by plants and weather, you are in on the gossip and can truly feel more at home. The sum of a field's forces becomes what we call very loosely the 'spirit of the place'. To know the spirit of a place is to realize that you are part of a part and that the whole is made of parts, each of which is whole. You start with the part you are whole in."

From "The Place, the Region, and the Commons" by Gary Snyder, published in The Practice of the Wild