One of the main ways Mississippian societies differed from earlier societies in eastern North America was in their much heavier reliance on maize agriculture for subsistence. There had been agriculture, and even maize, before in the east, but the Mississippians farmed much more intensively and used maize in particular much more heavily than people had before. The high productivity of maize agriculture presumably led to the increased population and more elaborate societies characteristic of the Mississippians, and also would have provided a dependable basis for the incipient urbanism seen in the biggest Mississippian centers like Cahokia. While maize had been introduced (ultimately from Mesoamerica and probably via the Southwest, although the details remain murky) to parts of the Eastern Woodlands hundreds of years before the rise of Mississippian societies after AD 900, it was only with the so-called “Mississippian Emergence” that it became a staple crop. The amount of maize typically found at archaeological sites in the east skyrockets after the Emergence, and intensive use of this crop seems to be a fundamental characteristic of the Mississippian lifeway.
Most of this has been known for a long time, based on the amount of maize found in Mississippian sites, but actually identifying and studying the fields where maize and other crops were grown had to wait until the incorporation of aerial photography into Midwestern archaeology in the 1960s. An important early contribution to knowledge of these issues is a paper published by Melvin Fowler in 1969. Fowler reports on work done by Southern Illinois University over the preceding few years at Mississippian sites in that incorporated aerial photography. He focuses on two sites specifically: the Lunsford-Pulcher site, a secondary mound center about 7 miles south of Cahokia, and the Texas site, a smaller farmstead on the Kaskaskia River about 50 miles east of Cahokia.
In both cases, aerial photography indicated the presence of parallel ridges that were not obvious on the ground in the proximity of the main architectural components of the sites. Surface collection of artifacts indicated a particular association between these ridges and fragments of the flaked-stone hoes that are very common at Mississippian sites, strengthening the hypothesis that the ridges indicated fields. Excavation further confirmed the hypothesis, revealing that the ridges consisted of dark topsoil piled up and revealing the lighter subsoil between the ridges. The narrowness of the ridges further indicated that they were definitely prehistoric and not the result of historic plowing. Fowler also refers to evidence from excavations in the 1930s at Ocmulgee National Monument, a major Mississippian center in Georgia, that revealed very similar ridges beneath at least one mound. This indicates that rather than an idiosyncratic practice in southern Illinois these ridges were a widespread Mississippian trait, apparently connected to hoe agriculture. He also refers to historical accounts from the nineteenth century indicating that similar ridged fields covered vast areas of Wisconsin and Michigan before white settlement.
The exact reason for the ridges was unclear to Fowler, and he offered just a few tentative ideas. It could have been a development stemming from the adoption of hoes, which would have been more effective than the digging sticks used previously and may have made it easier to pile up good soil for planting. The linear ridges of Mississippian agriculture may have been more efficient than the small hills used previously and associated with the use of the digging stick rather than the hoe. They may also have contributed to a more effective distribution of water to the plants; irrigation would not have been necessary in this wet climate, but a more efficient use of the copious rainfall may have been beneficial. It is also possible that the ridging allowed the use of low-lying land along rivers that would otherwise have been too swampy for planting. The two Illinois sites are certainly in locations where this would likely have been a factor, although Fowler notes that this is not the case for all the other reported areas with ridged fields.
Overall, this is an interesting study pointing out the advantages of aerial photography for identifying subtle archaeological features that may not be apparent on the ground. I am reminded especially of the Chaco road system, which was similarly identified via aerial photography a few years later. Also, and this has nothing to do with this particular article, I was interested to see the following notice in a box at the end of the last page:
NOTICE TO AUTHORS
A formal review procedure for all papers submitted to American Antiquity is being initiated. Papers will be evaluated by two referees; authors will receive copies of referee comments (unidentified as to source). Beginning immediately, THREE COPIES of all articles and submissions to Facts and Comments must be submitted. Contributions will not be considered for publication unless submitted in triplicate. Address inquiries to the editor-elect, EDWIN N. WILMSEN, Museum of Anthropology, Universitv of Michigan, Ann Arbor, Michigan, 48104.
Peer review was slow to catch on in archaeology, it seems.
Fowler, M. (1969). Middle Mississippian Agricultural Fields American Antiquity, 34 (4) DOI: 10.2307/277733