The Columbia Plateau and Its Artists
THE COLUMBIA PLATEAU EN-compasses the watershed of the Columbia River and its major tributaries (excluding the upper Snake River in southern Idaho) and the drainage of the Fraser River in south-central British Columbia (map 2). The region is bounded on the west by the Cascade Range, on the north by the divide between the Mackenzie and Fraser rivers, on the south by the northern Great Basin, and on the east by the Rocky Mountains. The plateau has a mild, dry continental climate with hot summers and cold winters. Temperature extremes range from –30 to 105 degrees Fahrenheit. Winters often have heavy snows, especially in the mountains; rain falls primarily in the spring and fall with occasional summer thunder-showers.
The northern Columbia Plateau is heavily forested with dense stands of fir and pine. Rushing streams and major rivers flow through narrow valleys that trend north to south. Numerous long, narrow, deep lakes (e.g., Flathead, Chelan, Priest, Kootenay, and Arrow) occupy glacially scoured portions of these valleys in western Montana, British Columbia, northern Idaho, and northern Washington. Mountain ranges throughout the area are often steep and severely sculpted by glacial erosion.
The central and southern portions of the region are an ancient basalt plateau formed by successive lava flows extruded from Miocene volcanos between 10 and 30 million years ago. In some places the basalts are more than ten thousand feet thick. Along the Columbia and Snake rivers successive layers form basalt rimrocks that rise more than one thousand feet above the deeply cut rivers, forming Hells Canyon of the Snake River and the Columbia Gorge. Other major rivers in this part of the plateau, the Deschutes and John Day, also flow through deep, basalt-rimmed gorges. This part of the Columbia Plateau, more arid than the northern section, has typical vegetation of mixed short-grass and sagebrush prairie with scattered forests on uplands like the Wallowa mountains.
In the approximate center of the Columbia Plateau lie the channeled scablands ranging around Dry Falls near Coulee City. These prehistoric water courses, Hells Canyon on the Snake River, and the Columbia Gorge are all relict landscapes formed by immense floods from glacial lakes Missoula and Bonneville, which emptied during the melting and retreat of the Pleistocene glaciers twelve thousand to twenty thousand years ago (U.S. Geological Survey 1973).
Throughout the entire region, the most prominent topographic features are the steep sheer cliffs—basalt in the central plateau and granite, argillite, or metamorphic rocks in the surrounding mountains and foothills. On these cliffs, and in shallow rock shelters along lakeshores, streams, and ridge tops, are found more than 750 sites of the Columbia Plateau rock art tradition.
The Prehistoric Record Clovis Culture
Archaeological evidence indicates that humans first came to the Columbia Plateau approximately twelve thousand years ago (10,000 B.C.). (See fig. 2.) These earliest immigrants, coming across the Bering land bridge from Asia and then moving south along the flanks of the Rocky Mountains or the Pacific coast, encountered a virgin land filled with herds of mammoth, mastodon, giant bison, ground sloths, and camels. They wandered from place to place, stopping to kill and butcher animals and camp in sheltered locations. Evidence of these early hunters—the characteristic Clovis fluted and lanceolate projectile points—has been found at a few sites scattered throughout the region: on the Snake River plain in Idaho, at the Dietz site in the northern Great Basin of central Oregon, at Wenatchee, and along the Columbia and Snake rivers, demonstrating that the hunters lived throughout the area. In the Pacific Northwest, the Manis Mastodon site near Sequim, Washington, on the Olympic Peninsula, is a kill and butchering site of these early people. Radiocarbon dates indicate that the mastodon dismembered here was killed more than eleven thousand years ago.
From these sites and others elsewhere in the West, we know that Clovis people were highly successful mammoth and mastodon hunters who had a variety of tools suited to performing the many different activities needed for living in this wild land. Dates for these sites are uniformly between ten thousand five hundred and twelve thousand years ago. Although their mammoth-hunting contemporaries in Europe and central Asia had a well developed artistic tradition that included both portable art and the world-famous cave paintings of France and Spain, the Clovis hunters apparently left no evidence in North America that they made rock art or portable sculptures.
Windust Phase
Following the Clovis hunters’ initial immigration into the New World, a period of relative cultural stability lasted for almost three thousand years, although many of the large game animals, such as mammoth, camel, and giant bison, became extinct by ten thousand years ago. On the Columbia Plateau, projectile points show slight stylistic changes during this period. The characteristic Clovis fluted spear point gave way to a series of leaf-shaped and stemmed points called Windust. Named after a rock shelter in eastern Washington, where they were discovered, Windust points are radiocarbon dated to between approximately eight thousand and ten thousand five hundred years ago (8,500–6,000 B.C.). Living in the numerous rock shelters throughout the central Columbia Plateau, and in open campsites elsewhere, the Windust people, also nomadic hunters, preyed on deer, elk, birds, and small mammals. Salmon bones in the Five Mile Rapid site near The Dalles, dating about eighty-five hundred years ago, are evidence that salmon fishing was added near the end of this period.
Excavated materials from Windust Cave, Wildcat Canyon, Marmes Rockshelter, Lind Coulee, Five Mile Rapid, and other sites show that these early hunters had tool kits fully adapted to their seminomadic life style. Chipped stone tools included projectile points, knives, scrapers, choppers, and drills. Bone and antler artifacts included awls, eyed needles, fleshing tools, barbed points, beads, hammers, flakers, wedges, and atlatls.
Old Cordilleran Culture
After the Clovis and Windust period comes the Old Cordilleran culture (Cascade phase), dating from approximately eight thousand to sixty-five hundred years ago (6,000–4,500 B.C.) and demonstrating stylistic changes in artifact types. The characteristic bipointed Cascade spearpoint and edge-ground cobbles used for food processing best identify this period. Other chipped stone and bone tools remained essentially the same as in the Windust period; hunting and fishing continued to be the primary mode of subsistence, although ground stone tools also indicate the use of plant foods. Old Cordilleran people hunted deer, elk, antelope, mountain sheep, and birds; took salmon and fresh-water mollusks from the rivers; and collected and processed berries and tuberous plants such as camas.
2. A generalized chronology of cultures on the Columbia Plateau, with associated artifacts and rock art motifs.
The Cascade phase provides the earliest reliable evidence for the presence of art on the Columbia Plateau. In Bernard Creek Rockshelter, along the Snake River in Hells Canyon, a pigment-covered spall from the roof was recovered from a level dating to this period, and in south-central Oregon a petroglyph with abstract line designs was found partially buried by a deposit containing ash laid down sixty-seven hundred years ago by the eruption of Mount Mazama (Cannon and Ricks 1986; Randolph and Dahlstrom 1977). These two occurrences clearly indicate that Old Cordilleran people made rock art in the Pacific Northwest.
Cold Springs Phase
Following the Old Cordilleran culture comes a three-thousand-year period of significant change on the Columbia Plateau that archaeologists have named the Cold Springs phase. The earliest Cold Springs phase sites immediately postdate the eruption of Mount Mazama. Archaeological evidence throughout the three-thousand-year span (4,500–1,500 B.C.) indicates that the western United States was somewhat hotter and drier than before or since. Archaeologists refer to this climatic maximum as the Altithermal period.
On the Columbia Plateau, the Cold Springs phase is marked by the appearance of various large, side-notched, projectile points and of microblades in the northern portion of the region. Both of these technological innovations facilitated hunting and butchering. Notched projectile points could be made smaller than lanceolate points,