Forage Quality and Alfalfa Characteristics in Binary Mixtures of Alfalfa and Bromegrass or Timothy

Seeding a perennial grass with alfalfa (Medicago sativa L.) may provide benefits without significantly reducing forage quality. Our objectives were to determine if including a perennial grass with alfalfa influenced forage quality, and alfalfa quality, maturity, and morphological characteristics at each of three annual harvests. For 2 yr at two locations, alfalfa, alfalfa‐smooth bromegrass (Bromus inermis Leyss.), and alfalfa‐timothy (Phleum pratense L.) were sampled three times annually at bud to one‐tenth bloom stage of alfalfa. Mean stage by weight, mean stage by count, stem length, and shoot weight of alfalfa were measured. Crude protein (CP), acid detergent fiber, and neutral detergent fiber (NDF) concentrations were determined for each forage and for alfalfa. Seeding bromegrass or timothy with alfalfa reduced CP on average 13% and increased NDF on average 12% at the first spring harvest, but not in subsequent harvests. Forage quality was higher for alfalfa grown with grass than for alfalfa grown alone at second harvest. Alfalfa component yield reduction in the mixtures was not directly proportional to grass yield. As a result, mixtures yielded more than alfalfa alone at the first harvest but less at the second harvest. Grass influenced alfalfa maturity, stem length, and shoot weight primarily at second harvest.