Most Iowa crop producers now rely on two crops, corn and soybeans, for their livelihood. This has led to many problems, including increased pest populations. Swine producers are interested in substituting dry field peas (Pisum sativum L.) for soybean meal in their swine rations because of the lower cost of peas and the ability to feed the peas without processing. A crop rotation study was begun in 2005 on the SE Iowa Research and Demonstration Farm near Crawfordsville, IA to compare the standard corn-soybean rotation to a corn-field pea/double cropped soybean rotation and a corn-soybean-winter wheat/double cropped field pea rotation. In addition to the small-plot crop rotation trials, large scale field trials of spring planted field peas followed by double cropped soybeans or grain sorghum and winter wheat followed by summer planted field peas were conducted from 2005 to 2007. In general yields have been poor with the summer planted peas, with the highest yield being 1300 kg/ha with the variety Admiral planted on July 28, 2005. This was likely partly due to the temperatures being too hot in August and September when the peas were flowering, and the growing season being too short in southern Iowa. A 30 hectare field of spring planted field peas averaged 2700 kg/ha followed by 1700 kg/ha of double cropped soybeans in 2005. Yields of spring planted peas were lower in 2006 than in 2005. A 10 hectare field of spring planted peas yielded up to 2500 kg/ha followed by 3600 kg/ha of double cropped grain sorghum in 2006. The field peas were utilized in swine feeding trials. No differences were found in average daily gain or feed efficiency in swine between the standard ration and a ration where part of the soybean meal and corn was replaced with peas.