Forage legumes increase nutritive value and provide N to grass‐based grazing systems. Few legumes have a long stand life in the southeastern US, but persistence is documented for rhizoma peanut (RP; Arachis glabrata Benth.). Several RP introductions have been released recently from the University of Florida, but their responses to grazing management have not been evaluated. The objective was to determine productivity, persistence, and nutritive value of three RP cultivars (‘Florigraze’, ‘UF Peace’, and ‘UF Tito’) and the germplasm Ecoturf grazed every 3 or 6 wk to remove 50 or 75% of pre‐grazing canopy height. Herbage accumulation (HA) was not different among RP entries and averaged 8790 and 6210 kg ha‐1 in Years 1 and 2, respectively. Greater HA occurred for the regrowth interval of 6 wk vs. 3 wk in the 50% removal treatment (8040 and 7010 kg ha‐1, respectively), and the response approached significance (P = 0.073) for the 75% treatment (7800 vs. 7140 kg ha‐1, respectively). Treatments had minimal effect on nutritive value, and all entries had crude protein (CP) ≥ 140 g kg‐1 and in vitro digestible organic matter (IVDOM) ≥ 660 g kg‐1. Grass encroachment was greater in Ecoturf and Florigraze when grazed every 3 wk (13 and 24%, respectively) than every 6 wk (7 and 15%, respectively), but regrowth interval did not affect grass percentage in Peace and Tito. New RP cultivars and germplasm had similar HA as Florigraze, but also greater percentage RP and lesser weed frequency than Florigraze, especially under frequent or close grazing.

‘Florigraze’ rhizoma peanut (RP; Arachis glabrata Benth.) is a persistent forage legume for the US Gulf Coast, but peanut stunt virus (Cucumovirus spp.) reduces herbage accumulation (HA). Less susceptible germplasms and cultivars of RP have been released, but their responses to grazing management are not known. The objective was to quantify aboveground and belowground sward responses to grazing management of RP entries differing in growth habit to explain HA and persistence. Treatments were all combinations of four RP entries (Florigraze, ‘UF Peace’, ‘UF Tito’, and germplasm Ecoturf), two grazing intensities (50 and 75% removal of pre‐grazing canopy height), and two regrowth intervals (3 or 6 wk). UF Tito swards were the tallest and Ecoturf the shortest, but Ecoturf had greater herbage bulk density than any entry. Pre‐grazing leaf percentage was greatest for Ecoturf (61%); there were no differences among the upright entries (56–57%). Ecoturf (0.88) and UF Tito (0.76) had greater post‐grazing residual leaf area index than Florigraze (0.61). Ecoturf and UF Tito had greater rhizome‐root mass (4450 and 4110 kg ha‐1, respectively) than Florigraze and UF Peace (3490 and 3170 kg ha‐1, respectively). Pre‐grazing light interception was greater for the 6‐ than 3‐wk grazing frequency (85 vs. 70%, respectively), and rhizome‐root mass followed a similar pattern (3990 vs. 2730 kg ha‐1, respectively). Sward structure, leaf, and rhizome‐root data explain lack of differences among entries in HA, excellent persistence of Ecoturf and UF Tito, and generally greater HA and persistence for 6‐ vs. 3‐wk regrowth intervals.

2377ReseaRch S easonality of forage production is a major challenge facing pasture-based livestock production systems throughout the world. The lack of forage for grazing in the season of shortfall requires supplementation as hay, silage, or concentrate, which increases the cost of livestock production. In central and south Florida, forage quantity limitations most often occur during winter, when cool temperatures and short days limit plant growth of most warm-season perennial grasses. However, the cool season is often not long enough to justify use of cool-season grasses as a forage source. Extending the length of the grazing season of warm-season forages can reduce the need for supplementation. This can be achieved by using cold-tolerant species or cultivars that remain productive after temperatures and day length begin to decrease or alternatively by stockpiling forage for use in winter.Limpograsses have demonstrated ability to produce more forage during the cool season than any other warm-season perennial grass adapted to Florida (Quesenberry et al., 2004). In

Wild pigs (Sus scrofa) have expanded their range in Brazil since late 1980s, with reports of damage becoming more frequent in recent years. In 2013, use of lethal methods for wild pig control was legalized by the federal environmental agency. However, several restrictions related to the purchase and transportation of guns and ammunition hamper the ability to evaluate the effectiveness of control measures. Nevertheless, many citizens engaged in wild pig control in Brazil do not officially report their control activities as required by the legislation. Our goal was to characterize the profile of wild pig controllers in Brazil to understand their methods and motivations, estimate the number of wild pigs killed per person per year, and evaluate current regulations regarding their applicability to the situations observed in the field. We formulated and distributed a structured questionnaire distributed in 2014 and 2015 to pig controllers (n ¼ 172), including both hunters and nonhunters. Respondents reported killing 2,389 wild pigs, and killing an average of 17.2 (SE ¼ 24.8) pigs/respondent/year, with male and female pigs killed in the same proportion. Forty percent of respondents were acting illegally. Hunters primarily controlled wild pigs to defend third-party properties. Volunteers provided most of the effort toward controlling wild pigs in Brazil and farmers suffered most of the impacts. Therefore, we believe that adjusting the approach to use of hunting after crop harvest, or implementing an integrated program of hunting and traps placed around crops, could be an important new management tool for reducing wild pig population and crop damage. Further, to enhance wild pig control in Brazil, we recommend incentivizing use of corral traps and cages because such techniques have the greatest effect on reducing wild pig population. Ó

No abstract

Limpograss [Hemarthria altissima (Poir.) Stapf et C.E. Hubb.] is a C4, perennial, stoloniferous grass that is well adapted to poorly drained soils and grows throughout frost‐free periods during winter in southern Florida. Its use has increased rapidly in recent decades, but nearly all area in cultivation is planted with one cultivar, ‘Floralta’. A breeding program was initiated to develop improved alternatives to Floralta, resulting in a group of breeding lines requiring evaluation under grazing. The objective of this research was to evaluate the performance of five limpograss breeding lines (1, 4F, 10, 32, and 34) under combinations of grazing frequency and intensity. During the 2012 and 2013 growing seasons, those lines, plus Floralta, were tested at two pre‐grazing canopy light interception levels (80 and 95%), that triggered the initiation of each grazing event, and two post‐grazing stubble heights (20 and 30 cm). Lines 4F and 10 had greater herbage accumulation, apparent herbage harvested, and persistence than Floralta. Initiation of grazing at 80% canopy light interception resulted in more frequent grazing events, a longer grazing season, shorter pre‐grazing canopy height, greater leaf percentage, less herbage bulk density, and greater herbage crude protein concentration compared with 95% canopy light interception. These data support cultivar release of breeding lines 4F and 10 and suggest that persistence and efficient utilization of limpograss under rotational stocking can likely be achieved by initiating grazing at a pre‐grazing canopy height of ∼60 cm, well before 95% canopy light interception, and by ending grazing at a post‐grazing canopy height of ∼30 cm.

The Cynodon spp. collection maintained by United States Department of Agriculture National Plant Germplasm System (USDA-NPGS) has limited information on nutritive value (NV) traits. In this study, crude protein (CP), phosphorous concentration (P), in vitro digestible organic matter (IVDOM), and neutral detergent fiber (NDF) were determined to (i) estimate genetic parameters for NV, (ii) obtain genetic values for the whole population across two harvests, (iii) estimate genotype by harvest interaction (GHI) for NV traits, and (iv) select accessions exhibiting improved NV traits compared to ‘Tifton 85′. The experiment was setup as a row-column design with two replicates and augmented representation of controls: Tifton 85, ‘Jiggs’, and ‘Coastal’. The whole-population was harvested twice, and data were analyzed using linear mixed models with repeated measures. In addition, a selected population of 15 genotypes were evaluated across 11 harvests to determine the extent of GHI. Genetic parameters revealed the presence of significant genetic variability, indicating potential improvements for NV through breeding. Specifically, P and IVDOM presented large variation, while NDF had lower diversity but some accessions exhibited lower NDF than Tifton 85. Low GHI, except for IVDOM, indicated genotypic stability and potential for selecting improved accessions under fewer harvests. Breeding line 240, PI-316510, and PI-3166536 presented superior NV than Tifton 85.

Seasonality of production limits when warm-season grass biomass can be provided to the bio-refinery. Delaying harvest after occurrence of a freeze extends this period, but the utility of this practice depends on its effect on biomass yield and composition. The objective was to quantify the effect of delaying harvest after first freeze on biomass dry matter (DM) harvested and composition of two perennial grasses. During a 3-yr experiment, elephantgrass (Pennisetum purpureum Schum.) and energycane (Saccharum spp. hybrid) were harvested shortly before or immediately after first freeze plus an additional two to three times during the subsequent 50 to 60 d in northern Florida. Extending the harvest period did not affect energycane biomass yield (avg. 27.6 Mg DM ha -1 ) during 2 yr, but elephantgrass yield decreased on average from 30.7 to 21.5 Mg DM ha -1 as harvest was delayed. Elephantgrass biomass DM concentration was greater than energycane (377 vs. 356 g kg -1 , respectively, in Year 1; 515 vs. 370 g kg -1 , respectively, in Year 2). Concentrations of cell wall constituents in both grasses increased as harvest was delayed after freezing, and the increase was generally greater for elephantgrass than for energycane. Delaying harvest of energycane after a freeze is effective in increasing the period when biomass can be supplied to the bio-refinery, but elephantgrass is less well suited for this management approach because biomass harvested declines with time after a freeze event.