Greenhouse and field experiments were conducted at the High Plains Grasslands Research Station to determine what might cause tetany-prone forage. The soil was analyzed for ammonium acetate-extractable cations, cation exchange capacity, and alkaline earth carbonates; and the successive harvests of forage plants were analyzed for magnesium (Mg), calcium (Ca), potassium (K), and nitrogen (N). Forages used in the study included legumes: 'Lutana' Cicer milkvetch (Astragalus cicer L.), 'Remont' sainfoin (Onobrychis viciafolia Scop.), 'Dawson', 'Vernal', 'Team', and 'Fremont' alfalfas (Medicago sativa L.); and grasses: 'Latar' orchardgrass (Dactylis glomerata L.), 'Fawn' tall fescue (Festuca arundinacea Schreb), 'Regar' bromegrass Bromus biebersteinii Roem & Schult.), 'Manchar' smooth bromegrass (Bromus inermis Leyss), 'Garrison' creeping foxtail (Alopercurus pratensis L.), 'Luna' pubescent wheatgrass [Agropyron trichophorum (Link) Richt.], and 'Greenar' intermediate wheatgrass [Agropyron intermedium (Host) Beauv.]. Forage Mg level increased when average soil temperature increased from 16.6 to 22.7 degrees C. Fertilization with 1,134 kg of Mg as MgSO4/ha did not increase forage Mg level. Later orchardgrass and Fawn tall fescue consistently produced forage containing more than 0.20% Mg, whereas wheatgrass species produced forage with Mg levels as low as 0.11%. All legumes had Ca levels ranging from 1.0 to 2.5%. One field crop of Later orchardgrass produced forage with a high K accumulation (K/Ca + Mg ratio of 2.7). Predication of blood-serum Mg from forage nutrient content indicated values from 17 to 31 mg/l in lactating cows. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.