Herbage Accumulation, Persistence and Nutritive Value of C ₄ Grasses Grown Across Temperate Environments in South‐Eastern Australia

Climate modelling has projected increasing temperatures and a shift in rainfall systems in southern Australia, suggesting an increase in the summer–autumn feed gap of pasture systems based on temperate species. Tropical (C 4 ) pasture species may diversify the feed base and help mitigate climate variability in these areas. In this study, we compared the herbage accumulation, persistence and forage nutritive value of eight tropical pasture species with those of locally adapted temperate species across eight sites in New South Wales (NSW) traditionally considered marginal for tropical pastures. Tropical grass species proved to be more persistent and productive than many temperate species in drier environments. Rhodes grass ( Chloris gayana Kunth.) cvv. Katambora and Reclaimer consistently ranked in the top five cultivars at these sites, while panic grass ( Megathyrsus maximus Jacq.) B.K Simon & S.W Jacobs cv. Gatton performed well at individual sites. At the wetter sites, tropical grass cultivars were productive, however were outperformed by temperate species. Forage metabolisable energy content ranged from 7.2 to 10.2 MJ/kg DM among tropical grasses, while energy varied in the temperate species from 5.4 to 13.2 MJ/kg DM across seasonal sampling. All tropical species had adequate mineral concentrations of calcium (range 0.35%–1.95%), magnesium (range 0.12%–0.39%) and phosphorus (range 0.24%–0.36%) to meet the needs of grazing ruminants. The exception was sodium, which was deficient (< 0.06%) in digit grass ( Digitaria eriantha Steud.), kikuyu ( Cenchrus clandestinus (Hochst.ex Chiov.) Morrone.) and bahiagrass ( Paspalum notatum Flüggé). Our study has shown that tropical grass species offer potential in the environments tested providing options for land managers to maintain year‐round feed production for livestock.