Chemical composition of ryegrass ( Lolium perenne L.) and prairie grass ( Bromus willdenowii Kunth) pastures

Abstract Herbage chemical composition, sward botanical composition, and animal intake were measured monthly for a year in pastures dominated by Lolium perenne (ryegrass) or Bromus willdenowii (prairie grass). Prairie grass was, on average, lower in phosphorus, magnesium, and sodium, but higher in potassium than the ryegrass. There were significant seasonal changes in herbage chemical composition for all the elements measured except sodium. The grass species sown did not affect overall animal intake of the elements measured, except that they were lower on the prairie grass pastures in mid spring.