Introduction, production, and persistence of five grass species in dry hill country

摘要

Production under sheep grazing from five grass species introduced into dry hill country, central Wairarapa, was compared with that from resident pasture. Treatments also included levels of nitrogen and phosphate fertiliser application, and three intensities of summer grazing. Mean annual herbage accumulation (HA) during the 5-year trial was greatest from phalaris (Phalaris aquaticaL. #x2018;Grasslands Maru') swards (10965 kg DM/ha). This was followed by resident swards dominated by ryegrass (Lolium perenneL.) (10040 kg DM/ha), swards sown with ryegrass (#x2018;Grasslands Nui#x2019;) (9050 kg DM/ha), prairie grass (Bromus willdenowiiKunth #x2018;Grasslands Matua#x2019;) (9040 kg DM/ha), cocksfoot (Dactylis glomerataL. #x2018;Grasslands Wana#x2019;) (8693 kg DM/ha), and tall fescue (Festuca arundinacea Schreb. #x2018;Grasslands Roa#x2019;) (8270 kg DM/ha). Variation in this order occurred for different years, seasons, and fertiliser and grazing treatments. Persistence varied between species, with the average sown grass species contribution in the fifth year being 77, 74, 31, 31, and 9 of HA for Nui, Wana, Matua, Maru, and Roa plots, respectively. The average response to fertiliser application was a 20 increase in annual HA, and responses to summer grazing management were generally small.