Effects of spring fertilizer nitrogen and sward height on production from perennial ryegrass white clover swards grazed by beef cattle

An experiment was carried out to compare the effects of two compressed sward height treatments, each at two fertilizer nitrogen (N) treatments (0 and 50 kg ha(-1) in spring), on the date of turnout and Liveweight gain of steers grazing a perennial ryegrass/white clover (Lolium perenne/Trifolium repens) sward sited on clay loam in south-west England. The sward height treatments were 6 cm all season, and 4 cm in the spring rising to 6 cm in June; these were maintained using continuously variable stocking with Hereford X Friesian steers. Cattle were turned out on average 11.5 days earlier on the 4-cm sward height compared with the 6-cm sward height treatment. Liveweight gain early in the season was lower on the 4-cm swards than on the 6-cm swards. Liveweight gain ha(-1) over the whole season was similar for the two sward height treatments. Fertilizer N did not affect turnout date or liveweight gain.