At Aztalan, Mississippian food production centered on agriculture, with people growing corn, squash, and other domesticated plants that were introduced to the area over the millennia, including squash as early as 1000 B.C. and corn around A.D. 1000. The earliest Euro-American visitors found remnants of ridged agricultural fields north of the outer stockade wall, though later plowing destroyed evidence of these ridges. Surrounding areas also supplied wild plant foods such as nuts, fruits and berries, roots, tubers, and more, adding tastes, textures, and nutritional elements to the community's diet. Intense crop production, supplemented by gathering, hunting, and fishing, created food surpluses that could be relied on during the lean winter months. Some foods were stored in pottery vessels for immediate use, while larger quantities were kept for later use in specially prepared storage pits identified throughout the site. Food production and the ability to create surpluses gave the people of Aztalan the resources needed to support ritual activities, craft specialization, and the construction of mounds, stockades, fish weirs, and houses.