Management and productivity of corn and alfalfa intercropping systems in the Southern U.S.

Agronomic intercropping systems involve growing grasses, legumes and row crops simultaneously in the same area to increase productivity, nutritive value, and economic viability. The purpose of this study was to determine the potential yield and nutritive value of corn (Zea mays L.) when intercropped with alfalfa (Medicago sativa L.) and crabgrass [Digitaria sanguinalis (L.)] to be used in silage production. These species were in a combination of corn (C), alfalfa (A), alfalfa + corn (AC), and alfalfa + corn + crabgrass (ACC) and was throughout the growing season of 2022 to 2024 at the Middle Tennessee Research and Education Center (MTREC) Spring Hill, TN. Samples were collected for forage mass (FM) and nutritive value. Alfalfa yield did not differ within the 2 growing seasons, but it differs within treatment (P < .05). The proportion of alfalfa was higher in 2023 than 2024 (P < .05). Crabgrass proportion was higher in 2024 than 2023 (P < .05). Corn yield was higher in 2023 than it was in 2024 (P < .05). Overall FM was greater in 2024 than in 2023. Alfalfa improved the crude protein (CP) content of the mixture while crabgrass improved neutral detergent fiber (NDFd).