Stockpiled Prairiegrass Provides High‐Quality Fall Grazing for Lambs

Abstract

New varieties of prairiegrass (Bromus catharticus Vahl. = B. willdenowii Kunth.) exhibit improved persistence over ‘Grasslands Matua’ under USA growing conditions, but animal performance data are lacking. We evaluated performance of lambs grazing stockpiled ‘Dixon’ prairiegrass on West Virginia hill pasture in autumn. In 2006 and 2007, a three‐year‐old stand of Dixon was cut for hay in late July, fertilized with 56 kg/ha of N, and stockpiled for eight weeks. Three pasture replicates of stockpiled forage were grazed by ewe lambs under a put‐and‐take grazing system for a total of 24 days (25 September to 19 October) with budgeted grazing intensities of 50% (GI50) or 75% (GI75) removal of forage mass. At the end of the grazing period, lambs were heavier (42.3 vs. 41.2 kg), and had greater average daily gain (ADG) (264 vs. 216 g/day) on the GI50 vs. GI75 treatment, respectively, but gain per ha was greater on the GI75 treatment (193 vs. 253 kg/ha). Fall grazing intensity did not affect forage mass, botanical composition, tiller density, or nutritive value of stands harvested for hay in the following May. Good forage mass production and excellent lamb gains on stockpiled prairiegrass indicate this grass deserves serious consideration for fall‐finishing of lambs.