EFFECTS OF LIME AND ALTITUDE ON THE PERFORMANCE OF PASTURES -BASED ON SIX ALTERNATIVE LEGUMES FOR ACID TUSSOCK GRASSLANDS

Abstract

Two lotus and 4 clover cultivars were oversown at 3 tussock sites ranging in altitude from 460 to 1040 m. The sites were initially similar in soil chemical characteristics, aspect and topography, so that differences were attributable mainly to increasing severity of climate. The objectives were to determine the extent to which legume choice is affected by(a) lime to raise so11 pH, and(b) increasing seventy of climate. In the first year'Grasslands Pawera' red clover wards were outstanding at the lower sites. With time the superiority of Pawera was overtaken by 'Grasslands Maku' and Maitland lotus. Maku swards were outstanding in the absence of lime (UP to 5.5 t DM/ha at 460 m. and up to 2 t DM/ha at 760 m) in years 2-3-4, and Maitland lotus swards produced up to 5 t DM/ha with lime at the lowest site, but did not perform well without lime. At the highest site. lotus-based pasture did not perform consistently as well as the white clover wards. At all sites lime greatly mcreased both the legume content of the swards and total pasture production for at least 4 years. Generally Maitland lotus gave the greatest and Maku lotus the least responses to lime. Keywords: lotus, clover, Maku, Maltland. Huia, Tahora. Pawera. Tetra, lime, altitude, tussock grasslands, legumes