Living mulch nutritive value in a corn-soybean-forage rotation
Living mulches can function to supply forage in multifunctional cropping systems. Information quantifying nutritive value of forage plants in living mulch cropping systems is limited. The objective of this research was to quantify the nutritive value of forages from different plant functional groups managed as living mulches in 2 of 3 yr and as a forage crop in the third year of this 3-yr corn (Zea mays L.)-soybean [Glycine max (L.) Merr.]-forage rotation. Alfalfa (Medicago sativa L.), Kura clover (Trifolium ambiguum M. Bieb.), and birdsfoot trefoil (Lotus corniculatus L.) were evaluated in sole seedings and binary mixtures, reed canarygrass (Phalaris arundinacea L.) and orchardgrass (Dactylis glomerata L.) were included in three-way mixtures, and a nondormant alfalfa was seeded each spring for comparison as a control. Average crude protein (CP) and neutral detergent fiber (NDF) during 2005, 2006, and 2007 was 190 and 449 g kg–1 for Kura + alfalfa + reed canarygrass compared with 182 and 458 g kg–1 averaged across birdsfoot trefoil + alfalfa + orchardgrass and Kura + alfalfa + orchardgrass mixtures, 195 and 397 g kg–1 averaged across alfalfa, Kura + alfalfa, and alfalfa + birdsfoot trefoil, and 193 and 404 g kg–1 for the nondormant alfalfa treatment. Weed densities averaged 104, 178, and 116 weeds m–2 in 2005, 2006, and 2007 among living mulch treatments compared with 14, 84, and 67 weeds m–2 in the nondormant alfalfa. Despite high weed densities in the living mulch treatments, no specific treatment effect was detected for nutritive value. All of these living mulch treatments produced high nutritive value forage.