Data from the the Wisconsin Integrated Cropping Systems Trial (WICST) show environmental advantages of using a chemical free three-phase system but yields were often lower than in the high input systems. We decided to test a ‘ChemLite’ approach adding reduced inputs to the 3-phase cash grain rotation and compare it to the three phase organic system (CS3), and the no-till corn soybean system (CS2). As posted by UW-Madison Center for Integrated Agricultural Systems.

The Neely-Kinyon LTAR site was established in 1998 to study the long-term effects of organic production in Iowa. Treatments at the LTAR site, replicated four times in a completely randomized design, include the following rotations: conventional Corn-Soybean (C-S), organic Corn-Soybean-Oats/Alfalfa (C-S-O/A), organic Corn- Soybean-Oats/Alfalfa-Alfalfa (C-S-O/A-A), and Soybean-Wheat (S-W).

Rotations of conventional corn-soybeans, organic corn-soybeans-oats/alfalfa, organic corn-soybeans-oats/alfalfa-alfalfa, and soybeans-wheat were evaluated. There were significantly fewer weeds in conventional corn plots but significantly lower stand counts in conventional soybean plots. Drought negatively affected both corn and soybean yields. No significant difference was found between organic and conventional yields. There were low pest populations. 2003 was the first year that organic soybean protein content was significantly higher than conventional. From Iowa State University.

The Neely-Kinyon LTAR site was established in 1998 to study the long-term effects of organic production in Iowa. Treatments at the LTAR site, replicated four times in a completely randomized design, include the following rotations: conventional Corn-Soybean (C-S), organic Corn-Soybean-Oats/Alfalfa (C-S-O/A), organic Corn- Soybean-Oats/Alfalfa-Alfalfa (C-S-O/A-A), and Soybean-Wheat (S-W). In 2005, there were significantly higher grass weed populations on June 15 and June 27 in the organic S-W soybean plots compared with all other rotations. There were significantly higher yields in both soybean and corn in the organic C-S-O/A compared with the conventional C-S rotation.

This study compares four organic and conventional crop rotations that includes corn, soybean, wheat, oats, and/or alfalfa rotations. Conventional corn plots yielded higher than organic plots. Some organic soybeans had significantly less staining than conventional and other organic soybeans. From Ohio State University.