The Plateau Culture
The term Plateau Indians is taken from the name of the Columbia Plateau. The Columbia Plateau is a region of highlands through which the Columbia River flows. Some 1,200 miles long, situated in both the United States and Canada, the Columbia River is one of the largest rivers in North America. It starts in the southeastern part of British Columbia, then flows a meandering route to the Pacific Ocean, forming much of the border between Washington and Oregon. It has many tributaries, including the Snake, Thompson, Okanagan,Deschutes, Umatilla, Willamette, and Kootenai Rivers. This system receives water from three mountain ranges—the Rocky Mountains, the Cascade Mountains, and the Coast Range. Another large river, the Fraser— also starting in the Rocky Mountains in British Columbia— is not part of the Columbia watershed.
What scholars define as the Plateau Culture Area is
situated between the Cascades to the west and the Rockies
to the east, the Fraser River to the north and the
Great Basin to the south. It includes territory now
mapped as southeastern British Columbia, eastern
Washington, northeast and central Oregon, northern
Idaho, western Montana, and a small part of northern
The mountains flanking the Plateau region—the Cascades
and the Rockies—catch a great deal of rain and
snowfall, making for the great number of rivers and
streams. The mountains and river valleys have enough
precipitation to support some of the tallest trees in the
world. These are evergreen forests of needle-bearing
conifers, including pine, hemlock, spruce, fir, and cedar.
The giant forests are too dense and shady for much
smaller vegetation to grow beneath them.
The Columbia Plateau has little rainfall, since the
Cascades block the rain clouds blowing in from the
ocean. The land consists mainly of flatlands and rolling
hills. Grasses and sagebrush are the dominant vegetation
in this part of the culture area.
The sparse ground vegetation of both mountain and
plateau meant little game for the Native peoples living
there. Some elk, deer, and bear could be found at the
edge of the forest. Some antelope and jackrabbits lived
out on the dry plains of the plateau. Yet the abundant
rivers and streams offered up plentiful food. Among the
many different kinds of fish were the salmon that swam
upriver from the ocean to lay their eggs. The river valleys
also provided plentiful berries, including blackberries
and huckleberries. On the grasslands of the plateau, the
Indians found other wild plant foods—roots and bulbs,
especially from the camas plant, a kind of lily; bitterroot;
wild carrots; and wild onions.
Through fishing, hunting, and gathering, Plateau
Indians could subsist without farming. In cold weather,
most Plateau Indians lived along rivers in villages of
semiunderground earth-covered pithouses, which provided
natural insulation. In warm weather, most peoples
lived in temporary lodges with basswood frames and
bulrush-mat coverings, either along the rivers at salmon-
spawning time or on the open plains at camas-digging
time. Plateau Indians also used the rivers as avenues of
trade, with many contacts among different tribes.