Herbage Accumulation, Nutritive Value, and Persistence Responses of Rhizoma Peanut Cultivars and Germplasm to Grazing Management

Abstract

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.