Grasslands Kahu timothy: quality pasture for animal performance

Abstract

<jats:p>Evaluations of Kahu timothy (Phleum prutense L.) included agronomy under mowing (1976-1979) and grazing (1980-1983), and animal performance from grazed pasture (1988-1993) and silage feeding (1989-1991). Agronomic testing showed that Kahu timothy was slow to establish, producing only 28% of the Grasslands Ruanui ryegrass (L.&amp;urn perenne L.) swards in the 6 months after sowing. Frequent, close defoliation severely reduced the yields of timothy and caused losses of plants, reducing longevity. A less frequent defoliation regime with a residual sward height of 30-50 mm gave the greatest sustainable yields. Under mowing Kahu produced significantly less than S51 timothy in summer and winter but under grazing Kahu was superior in spring and summer, resulting in significantly greater annual production. Animal performance testing showed hoggets grazing timothy in spring grew at 218 g/day, significantly greater than the 164 g/day achieved on Grasslands Nui ryegrass. The spring stocking rate on timothy was also significantly greater than on ryegrass, though utilisation of the forage was similar. When fed timothy/red clover silage lambs fed in winter grew at 98 g/day while lambs on standard ryegrass/ cocksfoot/white clover silage averaged a growth rate of only 44 g/day. From the assessment of the physiological state of individual tillers it was observed that timothy had a significantly higher proportion of its tillers with growing points present above ground through late spring and summer than ryegrass. This is suggested as a major reason for the depletion of timothy populations -under close grazing. When grazed correctly in late spring and summer timothy can provide a perennial forage of high feeding value for livestock systems. Keywords: animal performance, Grasslands Kahu, pasture quality, Phleum pratense</jats:p>

Sowing strategies for slow-establishing pasture species on a North Otago dairy farm

“…Red clover, with a heavier seed and a lower Tt requirement for emergence than white clover (about 120 °Cd) (Moot et al 2000), demonstrated seedling growth comparable with ryegrass at 43 DAS. A high Tt requirement for emergence (about 230 °Cd) (Moot et al 2000) and a low seed weight also provide explanations for the traditional classification of timothy as a slow-establishing pasture species (Sangakkara & Roberts 1981;Stevens et al 1993;Andrews et al 1997). In this experiment, timothy was successful as the sole grass species but was sensitive to competition from the lowest seeding rate of ryegrass.…”

“…Maximising animal production through increased intake of high quality pasture species is a recurring theme of sheep (Everest & Scales 1983;Brown 1990;Stevens et al 1993) and dairy (Harris et al 1997) research. Traditionally, high quality pasture has been characterised as that containing a high white clover (Trifolium repens) content (Rattray et al 1987).…”

Base temperature and thermal time requirements for germination and emergence of temperate pasture species

“…The Tt, and Tt requirements for emergence (Table 4) provide an explanation for the traditional classification of timothy and cocksfoot as slow establishing pasture species (Sangakkara & Roberts 1981;Stevens et al 1993). Both species had high Tt requirements and low seed weights and produced the smallest seedlings.…”

Yield reductions in agricultural grasslands in Norway after springtime grazing by pink‐footed geese

“…Hence, in the longer term, the plants will be weakened, and due to a slow rate of tillering and recovery, timothy is known to have a rather low tolerance to frequent defoliation regimes or grazing (Østrem & Øyen ; Stevens et al . ), especially if vegetative tiller apices are removed (Höglind, Schapendonk & van Oijen ). The present study was an experiment in which vegetation and yields were compared between exclosure plots, where the aim was to prevent or reduce goose grazing, and control plots open to goose grazing at four different perennial leys in central Norway.…”