The preceding analysis of plant remains from three archaeological sites that span the Late Prehistoric and Historic periods has produced some useful working hypotheses about the effects of European-Indian interaction on aboriginal subsistence practices. Differences in the amounts of various nut remains (e.g., more acorn and walnut relative to hickory at the later sites) may indicate a trend toward displacement of already low-ranked resources because of increased time and energy devoted to trade-related activities, principally deer hunting. In other words, the opportunity costs of exploiting certain low-ranked plant resources would have increased as trade-related activities increased. If corn remained important, as evidence so far suggests, its persistence in Piedmont subsistence may have been due to its role as a high-ranked staple not easily substituted by European domesticates or other traditional aboriginal foods. An apparent decline in "cool season" grasses is not easily explained in terms of changing costs and benefits, since these species would have continued to constitute a valuable resource during a part of the year when most other plant foods were unavailable. Scheduling conflicts resulting from trade activities or information loss about traditional plant procurement techniques are two possible explanations for such a decline. Adoption of the peach, a European introduction, was certainly related to low procurement and processing costs of this plant, as well as to its high energy returns and palatability.
Despite the differences noted between pre-contact and post-contact plant use, there is no evidence at the Fredricks site of adoption of European crops (except peach) or abandonment of native ones, and there is only moderate evidence of adjustments in the proportions of native plant foods contributing to subsistence. Perhaps the presumed position of Occaneechi Town as a trading center made it atypical in this respect. For example, if individuals from other depopulated areas aggregated at this village, its pre-contact population level might have remained stable despite losses through disease. And if Occaneechi men acted as middlemen in the European trade network, they may not have traveled far afield to hunt specifically for trade. We may find that the apparent stability of subsistence as revealed archaeologically in fact reflects a considerable amount of behavioral change (Winterhalder 1980). Behavioral changes may have been necessary to maintain the traditional diet represented archaeologically in the face of considerable peturbation.
In future research, we should look beyond the Piedmont to other parts of the East for comparisons of subsistence change and possible correlations between contact and aspects of change in other areas. Archaeological data on changing plant use in the Historic period are still not abundant (except, for example, Chapman and Shea 1981; Caddell 1981). As more data become available, however, it will be possible to profitably ask questions about variability in the effects of contact on subsistence. For example, were highly complex societies such as the Southeastern chiefdoms more resistant to change than simpler groups? Was change in subsistence more prevalent where trade with Europeans was most intense? Is depopulation really associated with "loss" of some traditions? Was subsistence change more rapid in areas where European settlers, as opposed to traders and travelers, were present as competitors for local resources? With regard to other effects of colonization, we might ask whether groups in heavily missionized areas such as Spanish Florida changed their subsistence practices more rapidly in response to pressures from European authorities. All of these questions are important ones, although they cannot yet be answered. However, studies focused on limited areas, such as the North Carolina Piedmont, will ultimately provide a basis for moving forward.