RESEARCHB ahiagrass (Paspalum notatum Flügge) is the main forage used for the beef cattle industry in Florida because of its reliability and persistence under adverse climatic conditions and management practices. It is the most widely planted warm-season grass in Florida, covering approximately 1 million ha. Nonetheless, overdependence on bahiagrass pastures has made the industry vulnerable to potential losses from pests and diseases. During 1996 through 2000, >150,000 ha of bahiagrass pastures were damaged by mole crickets (Scapteriscus spp.) in Florida (Adjei et al., 2001). Damage to bahiagrass pastures by mole cricket stimulated a search for other grasses adapted to the Florida environment.Brachiariagrasses are the most widely grown forages in tropical America, occupying >80 million ha (Boddey et al., 2004). Brachiaria species are popular among producers because they show rapid regrowth and good persistence under close or frequent defoliation (Rika et al., 1991). 'Mulato' is the fi rst hybrid in the Brachiaria genus and results from crossing ruzigrass (Brachiaria ruziziensis Germain & Evrard, clone 44-6) and palisadegrass [Brachiaria brizantha (A. ABSTRACTBahiagrass (Paspalum notatum Flügge) is the most used forage for beef cattle (Bos sp.) in Florida; however, damage to bahiagrass pastures by mole cricket (Scapteriscus spp.) stimulated a search for other adapted grasses. The objective of this study was to test the effect of different stocking rates (SRs) on animal performance and herbage characteristics of 'Mulato' (Brachiaria sp.) and bahiagrass pastures. The experiment was conducted in Ona, FL, from May to September, 2007 and 2008. Treatments were three SRs (4, 8, and 12 heifers ha −1 ) and two forage species (Mulato and 'Pensacola' bahiagrass). There was a linear decrease in herbage mass (from 5.9 to 3.2 Mg ha −1 ) and herbage allowance (from 2.8 to 0.6 kg dry matter kg −1 liveweight) with increasing SR. Mulato had greater in vitro digestible organic matter concentration than bahiagrass (675 vs. 534 g kg −1 ) but similar crude protein concentration (130 g kg −1 ). There was a linear decrease in average daily gain (from 0.49 to 0.22 kg d −1 ) and a quadratic response of liveweight gain ha −1 as SR increased (190, 353, and 217 kg ha −1 for SRs of 4, 8, and 12 heifers ha −1 , respectively). Mulato has potential to be an alternative forage to bahiagrass for beef cattle producers in Florida.

‘Mulato II’ (Brachiaria sp.) is a warm‐season forage hybrid with superior nutritive value introduced in Florida in 2003. The objective of this study was to evaluate the effects of harvest frequencies and stubble heights on herbage accumulation (HA), nutritive value, and persistence of Mulato II brachiariagrass. The research was conducted in Ona, FL (27°N) from August to October 2007 and 2008. Treatments were the factorial combination of 2‐ and 4‐week harvest frequencies and 1‐, 3‐, and 5‐inch stubble heights with four replicates in a randomized complete block design. Plot size was 9.8 × 6.5 ft with 3.0 ft between plots. There was a quadratic decrease in HA from 1,800 to 1,400 lb/acre with increasing stubble heights. Conversely, herbage crude protein (CP) and in vitro digestible organic matter (IVDOM) increased linearly with decreasing stubble heights (from 17% to 14% and from 67% to 66% for CP and IVDOM, respectively). There were significant season effects on responses as HA decreased and nutritive value increased from September to November for both harvest frequencies. Mulato II ground cover linearly increased from 74% to 87% as stubble height increased from 1 to 5 inches. Despite greater HA and nutritive value, short stubble heights in combination with 2‐week harvest interval decreased the persistence of Mulato II and should be avoided.

No abstract