Because of the selective nature of grazing livestock, the use of whole plant samples to estimate the nutritional potential of forages may be misleading. During this 2-year study, the distribution of dry matter (DM), crude protein (CP) in vitro organic matter digestibility (IVOMD), and concentrations of P, K, Ca, Mg, Mn, Fe, Cu, and Zn were determined in the individual leaf blades, leaf sheaths, nodes plus internodes, and infloresences of creeping bluestem (Schizachyrium stoloniferum), lopsided indiangrass (Sorghastrum secundum), maidencane (Panicum hemitomon), and wiregrass (Aristida stricta) when they were in the anthesis stage of maturity. Most of the DM was in the nodes plus internodes (avg. 45%), while the leaf blades (avg. 18%) generally made up the smallest amount of the total plant DM. In a progression from the bottom to top of the plant the CP, IVOMD, and most of the mineral concentration of the different leaf blades, sheaths, and nodes plus internodes increased. Crude protein, IVOMD, and most of the minerals of the grasses were higher in leaf blades, followed by sheaths, and nodes plus internodes. When compared with other grasses, maidencane had a higher proportion of CP and minerals in the leaves and nodes plus internodes and a higher percentage of plant weight in these parts. Wiregrass was found to be similar to creeping bluestem and indiangrass in CP and most minerals, but IVOMD of wiregrass parts were lower. Dietary requirements for dry, pregnant cows for P, N, Mg, and Cu might not be met by any part of the 4 grasses, while apparently adequate levels of Fe, Mn, and Zn could be provided by each part. Leaf blades and infloresences had sufficient Ca concentrations for dry pregnant 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.