Bitterweed (Hymenoxys odorata) growing at two locations was sprayed with 2,4-D (1.1 kg acid equivalent/ha) during the spring of 1977. Subsequently, plants were collected, dried, and stored when they showed definite signs of herbicide phytotoxicity (epinasty and turgidity). Hymenoxon concentrations were determined on the dried plant material and it was force-fed to penned sheep, in two experiments, to determine the effect of foliar spraying with 2,4-D on bitterweed toxicity. Bitterweed administration decreased voluntary feed intake and increased serum concentrations of urea nitrogen (UN), creatinine (C) and glutamic-oxalacetic transaminase (GOT). Hymenoxon concentrations (air-dry basis) were 2.33 +/- .18% and 1.64 +/- .05%, for unsprayed and 2,4-D sprayed bitterweed, respectively, in Experiment 1 and 1.24 +/- .02% and 1.08 +/- .05%, respectively, in Experiment 2. Spraying bitterweed did not affect feed intake and serum levels of UN, C and GOT and there were not interactions between bitterweed levels and 2,4-D treatments. 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.