Palle Pedersen, John Sawyer, Jodee Stuart, and Daniel Barker. Iowa State University, 2104 Agronomy Hall, Ames, IA 50011-1010
Incorporation of perennial legumes into row cropping systems, in combination with reduced tillage, may help growers with soil erosion control and reduce production inputs. The overall objective of this project was to demonstrate that corn (Zea mays L.) and soybean [Glycines max (L.) Merr.] can be grown in a kura clover (Trifolium ambiguum M. Bieb) living mulch system while maintaining crop yields. The experimental design was a randomized complete block in a split-plot arrangement with three replications. Main plots were strips of kura clover and strips of prior-year corn or soybean. In 2004, kura clover was planted at six locations and allowed to established without planting row crops. In 2006, corn was planted at three locations and soybean at the other three locations. The corn and soybean were no-till planted into the kura clover and either previous corn or soybean stubble strips (without kura clover). Sub-plots at the soybean locations were seeding rates of 371 000, 494 000, 617 000, and 741 000 seeds/ha. Sub-plots at the corn locations were N rates of 0, 45, 90, 135, 180, and 225 kg N/ha. Overall, soybean yield was reduced 39% with planting into the kura clover living mulch system. Data from the plant population study was inconsistent to draw any conclusions. The kura clover living mulch system appeared to supply sufficient N to the corn crop, however, strip corn yields averaged 1444 kg/ha lower compared to the no kura clover living mulch. This research will continue in 2007.