Although plant remains from three sites are included in this study, comparison will focus on the Wall and Fredricks sites, which represent sequential occupations of the same approximate location. The Mitchum site occupation, temporally intermediate between the first two, is anomalous in certain respects. In fact, calculation of a similarity index (King 1982) based upon plant taxa (expressed as twice the number of shared taxa divided by the total number of taxa for both sites) shows greater similarity between Wall and Fredricks than between either of them and Mitchum. One reason for this distinctiveness is that some deposits at the Mitchum site display a seasonal profile different from those of the other two sites. This factor, as well as the location of Mitchum in a different river valley and the relatively small area of the site that was sampled, makes it difficult to assess change using all three sites. Therefore, the Mitchum site plant remains probably should not be considered representative of a transitional subsistence pattern in a developmental sequence from the Wall site occupation to that of the Fredricks site. Although the cultural connectedness of the Wall and Fredricks site populations is still in question, they shared a similar local environment and probably had a similar range of plant foods from which to choose. Comparison, therefore, will focus on the use of plant foods by these two populations.