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Rhizoma peanut (RP; Arachis glabrata Benth.) is an important perennial forage legume in the US Gulf Coast region, but propagation using rhizomes and prolonged establishment periods limit its adoption. Genotypes and management practices that hasten establishment are needed. Our objective was to determine the effects of RP growth habit and nitrogen (N) fertilizer application during shoot emergence on biomass partitioning and measures of establishment success during the year‐of‐ and year‐after‐planting. Field experiments were conducted during 2016 through 2018. Treatments were the factorial combinations of two RP entries differing in growth habit (decumbent germplasm Ecoturf and upright cultivar 'UF Tito') and three N rates (0, 40, and 80 kg/ha applied 10 weeks after planting [WAP]) arranged in four replications of a randomized complete block design. Upright UF Tito had greater shoot (194 vs. 125 g/m2) and root‐rhizome biomass (249 vs. 111 g/m2) than decumbent Ecoturf at the end of the year of planting. Early growth patterns explained this response in part, as UF Tito had greater leaf area index (LAI; 0.58 vs. 0.39) and lesser root‐rhizome: shoot ratio (0.62 vs. 0.77) than Ecoturf at 20 WAP. Nitrogen fertilization had minimal effects on shoot biomass, and it did not affect root‐rhizome biomass. The entry effect on establishment performance persisted through the year after planting with UF Tito outperforming Ecoturf. Use of an RP genotype that prioritized leaf area and shoot versus root‐rhizome biomass during early growth was more important than N fertilization in expediting RP establishment. [ABSTRACT FROM AUTHOR]

Warm-climate grasslands are often N limited. Legume litter decomposition can contribute significantly to N input in grazing systems, but its contribution depends on litter deposition, decomposition, and chemical composition. We evaluated these responses for 2 yr in unfertilized (BG) and fertilized (BGN; 50 kg N ha-1) bahiagrass (Paspalum notatum Flügge) monocultures and in mixed swards of bahiagrass plus the legume rhizoma peanut (Arachis glabrata Benth.). Legume-grass mixture litter had greater initial N concentration (26 g N kg-1 organic matter [OM]) and lower C/N ratio (22) than BG and BGN, which did not differ from each other (18 g N kg-1 OM, C/N ratio of 31). Litter biomass relative decay rate was greater for mixtures than for bahiagrass monocultures. As a result, less biomass and N remained at the end of incubation in mixtures (62 and 76%, respectively) than in monocultures (69 and 80%, respectively). Litter deposition rate was similar across treatments, but faster decomposition and greater N concentration for legume-grass mixtures resulted in larger litter N release than in monocultures (44 and 26 kg ha-1, respectively). At the end of incubation, remaining litter biomass and remaining N decreased with increasing litter legume proportion, whereas litter N concentration and litter decay rate increased. Results indicate that legume-grass mixtures are an alternative to N fertilizer for increasing N cycling through plant litter in grasslands, and although litter deposition rates were similar across treatments, increasing legume proportion in mixtures is likely to be associated with greater litter N release. [ABSTRACT FROM AUTHOR]