Design
Most Columbia River Plateau bags are classified according to one of two basic design categories. The first and oldest design category is geometric designs. Geometric designs are thought to have evolved as a function of the weaving process itself, which naturally encourages angular motifs like triangles, diamonds, rectangles, chevrons and lines. Although the individual components of geometric designs are simple, the many ways the different shapes can be combined often produces patterns that are highly complex and sophisticated. As Dr. Schlick noted, the repatriated bag falls into this category:
The design motifs and arrangement on this bag are consistent with those favored by Plateau weavers of the 19th century: vertical columns of stacked triangles and stepped motifs are common patterns; the designs on the two sides differ; a wandering left column is caused by the left-moving tendency of Z-twining.1
The second major design category found in Columbia River Plateau bags is figural designs. Figural designs encompass a broad range of representational forms that most often include human figures, animals, and plants. Because figural designs are much more difficult to create using traditional weaving techniques, they tend to appear mainly in small embroidered bags and in beaded bags.
In addition to distinguishing between geometric and figural designs, scholars also classify Columbia River Plateau bags according to the organization of the designs. The five most common categories of design organization are overall designs, banded designs, central designs, five-part designs, and naturalistic designs. The use of color is yet a third important factor that affects our perception and understanding of Columbia River bag designs, which is especially important to scholars in terms of dating.
1Z- or s-twining refers to the direction in which the fibers of the weft twist around each other. The directions correspond to the slant direction of a capital "Z" or a capital "S," thus a z-twined bag like the repatriated bag has wefts that twist from the upper right to the lower left.