Cattle Preferentially Select Birdsfoot Trefoil from Mixtures of Tall Fescue and Birdsfoot Trefoil

When birdsfoot trefoil (Lotus corniculatus L.) is interseeded into tall fescue (Festuca arundinacea Schreb.) pastures, animal performance often exceeds that expected based on forage samples taken from the pasture. This may be due to cattle (Bos taurus) preferentially selecting birdsfoot trefoil from mixed pastures. Our objective was to investigate the selectivity for birdsfoot trefoil by cattle grazing tall fescue‐birdsfoot trefoil pastures. Treatments were ‘Phyter’ tall fescue sown in a monoculture and in mixtures with ‘ARS‐2622’ and ‘Norcen’ birdsfoot trefoil. Beef heifers fitted with esophageal cannulas grazed pastures in the spring and autumn of 1998 and again in spring 1999. In the tall fescue‐birdsfoot trefoil mixtures, the amount of birdsfoot trefoil on‐offer showed a 73% reduction during the study, but the amount of birdsfoot trefoil in esophageal samples declined by an average of only 22%. Although the percentage of birdsfoot trefoil in mixed pastures often declines over time, its value may be underestimated because animals selectively graze this species when its proportion in pastures is low.