A nine-year comparison was made of pasture yields measured by the "mowing and clippings returned" and the "enclosure" techniques of yield estimation. Using the former technique, pasture yields declined at a rate of 270 to 360 kg/hn dry matter per annum. Using the "enclosure" technique (which includes the grazing animal) there was no change in pasture production with time. Both techniques detected significant responses to superphosnhate. Results from the "mowing and clinoinas returned" techniaue approximated absolute pasture production for a period of up to three years. The "enclosure" technique is considered to have provided a reliable. estimate of absolute production over the nineyear period.