Seasonal distribution of pasture production in New Zealand XX. North and East Otago downlands

Abstract

Abstract Pasture growth rates are presented for two dryland and one irrigated site on the downlands of North and East Otago, New Zealand. Growth rates were obtained from grazed pasture cut by the trim-cut method using movable cages. The mean growth rate and standard errors are given for standard cut dates at 14-day intervals. Soil water deficits, the result of low and variable rainfall, caused growth to be quite variable at the dryland, East Otago site. Mean annual production there was 8800 kg dry matter (DM)/ha. Dry conditions were more severe in the North Otago downlands, a district with a long history of drought. Consequently, growth rates were lowest there and, overall, averaged 80% of those recorded in East Otago. The irrigated site on the downlands margin in North Otago had an average annual production of 15 000 kg DM/ha, and a more uniform rate of growth throughout the drought-prone summer to autumn period. General climatological data, rainfall, and temperature records during the periods of pasture...