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Aeschynomene (Aeschynomene americana L.) is a warm‐season annual legume forage used in tropical and subtropical regions; however, there is limited information on agronomic and environmental benefits of aeschynomene when overseeded into bahiagrass (Paspalum notatum Flüggé) swards. The objective of this study was to evaluate the effects of overseeding aeschynomene or applying N fertilizer to existing bahiagrass on forage characteristics, atmospheric N fixation, and N2O‐N emissions. The study was conducted in Ona, FL, from April 2019 to March 2021. Treatments were the split‐plot arrangement of bahiagrass‐aeschynomene or bahiagrass monoculture (main plot) and N fertilization level (0 or 60 kg N ha−1; subplot), distributed in a randomized complete block design with four replicates. Nitrogen fixation was estimated in plots receiving no N fertilization. The static chamber technique was used to estimate N2O‐N emissions. Overseeding aeschynomene did not increase forage accumulation (mean = 1300 kg dry matter [DM] ha−1 harvest−1) or N2O emissions (mean = 15 g N2O‐N ha−1 per day), but increased forage crude protein (CP) concentration (from 98 to 108 g kg−1) when compared to bahiagrass monoculture. Nitrogen fertilization increased forage accumulation (from 1200 to 1400 kg DM ha−1 per harvest) but it did not affect aeschynomene N fixation (84% N derived from atmospheric fixation [Ndfa]). Nitrous oxide emissions had significant temporal variability across all treatments; however, there were no differences in accumulated N2O‐N emissions among treatments (mean = 2.4 kg N2O‐N ha−1 per year). Overseeding aeschynomene is an effective management practice to increase forage CP concentration in pastures without increasing N2O‐N emissions.

The objective of this study is to identify qualitative and productive changes in Mombasa grass under a livestock-forest system or full sun and to classify the variables that are most relevant for evaluating the qualitative performance of these systems. The experiments were conducted in shade areas, with four replications for each of the 12 treatments, including four growth cycles and three levels of shading in Mombasa grass, totaling 48 experimental units. Calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), nitrogen (N) and dry mass production (DMP) (kg ha -1 ) were used as discriminatory variables for the shading groups. The levels of nutrients and shading in Mombaça grass were classified using Fisher multivariate discriminant analysis (FMDA). The FDMA indicated that Mg, K, P, N, and DMP formed a discriminant function. However, DMP was the least important variable for identifying the groups. Five groups were pre-defined before FDMA: MFS 2 (Mombasa grass in full sun in the second cycle), MFS 6 (Mombasa grass in full sun in the sixth cycle), MFS 7 (Mombasa grass in full sun in the seventh cycle), M25 4 (Mombasa grass at 25% shading in the fourth cycle), and M25 7 (Mombasa grass at 25% shading in the seventh cycle). The results indicate that Mg, P, K, and N are helpful for identifying new genotypes of plants grown on shading conditions because of the responsiveness and stability of these elements to environmental changes. Key words: Cycles. Macronutrients. Multivariate. Panicum maximum. ResumoObjetivou com este estudo identificar as alterações qualitativas e produtivas do capim Mombaça em sistema silvipastoril e pleno sol, e classificar as variáveis mais estratégicas para avaliação do seu desempenho qualitativo. O ensaio foi alocado em faixas de sombreamento, com quatro repetições para cada um dos 12 tratamentos -quatro ciclos e três porcentagens de sombreamento, em capim Mombaça, totalizando 48 unidades experimentais. Foram usados os macroelementos: cálcio (Ca), magnésio (Mg), potássio (K), fósforo (P) e nitrogênio (N) e Produção de massa seca (PMS) (kg ha -1 ) como variáveis de

The objective of this study was to evaluate the concentrate supplementation frequency effects on forage characteristics and performance of early-weaned beef calves grazing annual ryegrass (Lolium multiflorum). The experiments were conducted in Ona, FL from February to April (Exp. 1) and June (Exp. 2) 2019 and 2020. In Exp. 1, thirty-two early-weaned calves (82±12 d of age) were allocated to 8 annual ryegrass pastures (4 calves/pasture) and supplemented with 1% BW. Treatments were 2 concentrate supplementation frequencies, daily (DAILY) or three times per week (3X; Monday, Wednesday, and Friday) distributed in a randomized complete block design with 4 replicates. Calves receiving the 3X treatment had the daily supplement level multiplied by 7 d and divided by 3 feeding days. Pastures (experimental units; 0.4 ha/pasture) were grazed with a continuous and fixed stocking rate. There was no difference in herbage mass (P = 0.85; mean = 3050 kg/ha), herbage allowance (P = 0.91; mean = 3.0 kg DM/kg BW), CP (P = 0.88; mean = 17.5%), and in vitro digestible organic matter (P = 0.82; mean = 74%). In addition, there was no difference in ADG (P = 0.60, mean = 0.65 kg/d), plasma urea nitrogen (P = 0.88; mean = 10 mg/dL), and glucose (P = 0.45; mean = 72 mg/dL). In Exp. 2, twenty early-weaned calves from Exp. 1 were maintained in the same treatment and placed in a drylot with individual stall for forage DM intake, total DM intake, and in vivo digestibility measurements. Treatments were the same described in Exp. 1 distributed in a randomized complete block design with 10 replicates. Calves receiving the DAILY treatment had greater forage DM intake (P = 0.02; 1.8 vs. 1.6% BW), total DM intake (P < 0.01; 2.7 vs. 2.5% BW), and in vivo digestibility (P < 0.01; 87 vs. 85%) than 3X. Feeding three times per week may be a feasible management practice to decrease the cost of labor related to feeding early-weaned beef calves.