A field trial to study the effects of soil fumigants on pure swards of 'Grasslands Huia' white clover growing in a yellow-grey earth infested with clover cyst nematode (Heterodera irijolii) , was run for 18 months. The treatments, replicated four times (24 plots, 2 x 1 m), were: control, methyl bromide, 'DD' soil fumigant at 300 l/ha, 'Nemagon' at 11.23 l/ha. 'Nemagon' at 22.46 l/ha, and 'Mocap' at 67 kg/ha. Twelve harvests were made during the trial and mean yield response to fumigation was 7.6% [-0.2% ('Nemagon' 22.46 I/ha) to 12.3% ('D.D.')]. However, during periods of activity of the clover cyst nematode yields were up to 46% higher in fumigated than in control plots. The effect was enhanced by moisture stress. Fumigation also extended the growing season into the summer drought.

The effects of two stocking rates (15 and 22 ewes per ha), two rates of lime (0 and 6300 kg.ha'), and two rates of superphosphate (125 and 500 kg.ha' annually) on incisor teeth wear were measured on the Wairarapa Plains near Masterton. Greater wear of teeth was incurred in ewes stocked at the higher rate, and most wear occurred during winter and spring when soil ingestion was greatest. Levels of vitamin B 12 , selenium, copper, iron, and zinc in livers were determined on four treatments on completion of the trial. Vitamin B I2 levels in the liver were higher on unlimed pastures at the higher stocking rate.

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Nine subterranean clover cultivars (Trifolium subterraneum L.) and 10 white clover lines(T. repens L.) wereevaluated for5 yearsunder conditions of regular summer drought and winter water-logging. Grazing management initially allowed an assessment of growth potential; regenerative ability was morerealistically assessed under typical farm management during the last 3 years of the experiment. Erect, open growing subterranean clover cultivars (e.g., 'Clare', 'Woogenellup') yielded the most under lenient cutting managements and where populations were artificially boosted by transplanting. After 3 years of farm grazing, 'Tallarook' had achieved the greatestseed and seedlingnumbers (7500and 330/ m 2 respectively). Allcultivars except 'SeatonPark', "Irikkala', and 'Woogenellup' achieved pasture coverinexcessof 30%by theendof theexperiment. This indicates thegeneralsuitability of subterranean cover to these site conditions. Despite replanting and lenient defoliation management during late spring-summer,no whitecloverlines satisfactorily persistedafter 3 years.

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