|Mitchell, Robert - Rob|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/1/2003
Publication Date: 11/1/2003
Citation: MITCHELL, R., VOGEL, K.P., ANDERSON, B.E., KLOPFENSTEIN, T., MASTERS, R.A. EVALUATION OF FOUR BIG BLUESTEM POPULATIONS UNDER GRAZING. AGRONOMY ABSTRACTS. 2003.
Technical Abstract: Two big bluestem (Andropogon gerardii) strains (Pawnee C3 and Kaw C3) developed by three cycles of breeding for increased digestibility and yield were compared to the base populations of 'Pawnee' and 'Kaw' in a 3 y grazing trial. Pastures were seeded in May 1998 near Mead, NE. Experimental units were three 0.4 ha pastures of each strain or cultivar in a randomized complete block design. Pastures were burned and fertilized with ammonium nitrate at 112 kg N ha-1 in the spring of 2000, 2001, and 2002 prior to grazing. Each pasture was stocked with three crossbred yearling steers ('300 kg) in mid-June 2000, 2001, and 2002 to provide a stocking rate of 7.5 steers ha-1. Pawnee C3 and Kaw C3 produced 15% and 8% more ADG, respectively, than the base populations during this 3-year study. Additionally, Pawnee C3 and Kaw C3 produced 14% and 8% more kg of beef per ha, respectively, than the base populations. Pawnee C3 increased ADG by 19% over the base population, and produced more than 380 kg of beef per ha during a drought period in eastern Nebraska. These improved strains are being increased for release as cultivars. Pawnee C3 and Kaw C3 are adapted to USDA Plant Hardiness Zones lower 4 & 5 and lower 5 & 6, respectively, east of 100 W. Long.