Grazing Management Affects Performance of Strip-Planted Rhizoma Peanut in Bahiagrass Pasture.

Establishing rhizoma peanut (Arachis glabrata Benth.; RP) in strips into existing bahiagrass (Paspalum notatum Flügge) pastures has the potential to increase forage nutritive value and animal performance and improve N cycling. Grazing the grass-legume mixture in the year after planting may be possible, but data on grazing management effects are needed. The objectives were to evaluate: 1) the effect of year-after-planting (Year 2; Y2) grazing management of bahiagrass swards strip-planted to ‘Florigraze’ RP on canopy cover, frequency, and spread, and 2) the interaction of defoliation strategies in the year of RP planting (Year 1; Y1) with Y2 grazing management of strip-planted bahiagrass swards. Treatments were the combinations of three Y2 grazing frequencies (continuous, 28 d, and 42 d to a bahiagrass stubble height of 15 cm) in combination with four Y1 defoliation strategies (no defoliation, hay production, simulated continuous stocking, and rotational stocking every 28 d). Grazing pastures in Y2 severely reduced RP contribution relative to that observed at the end of Y1. Canopy cover and frequency decreased from 30 to 10%, and from 80 to 50%, respectively, due to Y2 grazing for both the Y1 no defoliation and hay production treatments and remained below 10% in Y2 for both Y1 simulated continuous and rotational stocking treatments. Spread of RP into adjacent bahiagrass was greater in Y2 plots (~25 cm) that were not defoliated or were used for hay production in Y1 compared with those grazed in Y1 (~0 cm). The results indicate that defoliation strategies in the year of- and year-after-planting are critical to promote successful establishment of strip-planted RP and that grazing in Y2 using bahiagrass stubble height as a target end point has a negative impact on RP.