Researchers have long recognized a sequence of cultural patterns throughout the Pacific Northwest during the Early Holocene. On the Columbia Plateau the Windust and Cascade phases are recognized by distinctive material assemblages (Leonhardy and Rice 1970), and, according to Ames (1988: 356), by “clear evidence for different residential mobility patterns.” In the Northern Great Basin Bedwell (1973) and Cressman (1986) similarly divided pre-Mazama time (ie, before ca. 7600 years ago, and for purposes of the present discussion after ca. 12,000 BP) into two cultural periods. Based on evidence from Fort Rock, Connley, and other caves, the cultural assemblage of the early pre-Mazama period (ca. 12,000-9000 year ago) was reported to include the twined Fort Rockstyle sandals, and un-notched projectile points with ground basal margins. In the late pre-Mazama period (ca. 9000-7600 years ago),“[c] hange is undeniable in terms of artifact form and flaking, a greater emphasis on the use of obsidian, the greater use of unretouched flakes, and the addition of new tools”(Bedwell 1973: 159; cf. Cressman 1986). This time is also marked by an apparent decline in occupation intensity of the caves.

Being a relatively plastic medium subject to much stylistic variability, basketry (taken as a broad class to include sandals and other woven materials) has been particularly useful in considering cultural patterns and ethnicity in the Western US (Adovasio 1986; Adovasio and Pedler 1994; Fowler 1994; Geib 2000). In the Northern Great Basin, however, basketry has sometimes provided more controversy than clarity (Connolly et al. 1998). For example, Cressman (1986: 122) characterized early pre-Mazama time in the Fort Rock basin and vicinity as “the period of the woven sandals from Fort Rock Cave and of basketry with false embroidery.” Looking at the same set of data, Adovasio and his colleagues (Adovasio 1970, 1974, 1986; cf. Adovasio et al. 1976, 1986) concluded that “in all cases, the pre-Mazama-age basketry... is simple twined and undecorated.” They suggest that