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in this were: low or high rates of superphosphate application (plus lime and 3 grazing managements - rotational grazing by sheep or by cattle, and set stocking by sheep. pasture, and animal characteristics and measurement of pasture 'structure' was collected information on density of and of on the production of in when vegetation was by herbicide before sowing. Grazing management studies in hill country have frequently demonstrated similar white clover production under different sheep management systems. Intensive cattle grazing can, however, substantially improve white clover performance. One factor which may contri bute to these management effects is the defoliation pattern ofanimals under each system. This study was,conducted to deterrnine the extent to which defoliation patterns differed under set-stocked (SSS)and rotationally grazed sheep (RGS), and rotationally grazed cattle (RGC). Frorn this, it was possible to make inferences about the contribution ofdefoliation pattern (compared to the contribution of other environmental variables such as sward structure and composition) to clover performance differences. Therefore the potential for improving white clover contributions using other management systems could be pre dicted. The results were also used to estimate likely management effects on photosynthetic capacity of clover plants. Glasshouse and laboratory studies have demonstrated that the increase in soil pH caused by liming, increases the rate of breakdown of soil organic matter, thus releasing nitrogen (N). The present experiment was designed to measure the size of this effect in the field. Lime (7.5 t/ha) was applied once to a fertile volcanic ash soil (initial pH 5.7) in Tar anaki. The effects ofliming on total herbage production and soil N uptake were measured over 2 years. These that one of of machine milking stimulation. The advantages of determining pre-milking stimulus requirement time using machine milking action alone are that it can be measured directly, and it can be carried out in the field. A survey and several field trials in the Auckland and Waikato areas from 1980 to 1982 found that the green looper caterpillar Chrysodeixis eriosoma was the most common insect pest of soybeans. Spray trials showed that although it produced up to 15% defoliation this did not significantly reduce seed yields. Mechanical defoliation and cage experiments confirmed the ability of soybeans to compensate for up to 17%defoliation, and identified the seed enlargement stage as most susceptible. Estimates of economic injury levels showed that green looper populations were about half that required to cause significant damage. Tomato fruitworm Heliothis armigera, which normally feeds on fruiting parts of plants, occurred at low levels and damaged 5% of the pods but did not affect seed yield. The green vegetable bug Nezara viridula, frequently reported as damaging beans in warmer areas, was expected to be an important pest but was rare in this study. Ryegrass infected with the fungus Acremonium loliae has been shown to cause the animal disorder, ryegrass staggers. The fungus also confers, on infected plants, resistance to Argen tine stern weevil and improved growth. A simple rapid serological assay (ELISA) has been developed to detect the presence of the fungus in grass tissues. This paper defines con ditions for plant sampie preparation in which the major fungal antigen is made soluble under conditions where its serological activity is retained. This reduces sampie prepara tion time and improves quantification of the fungus. Endophytic fungi which form a close symbiotic relationship with ryegrass and fescue are associated with the animal diseases ryegrass staggers and fescue toxicosis. An antibody based assay (ELISA) has been developed for the detection of the fungi in grass tissues. This paper describes a method by which the major fungal antigen can be purified from culture filtrates. This has allowed highly purified antigen to be produced and subsequently characterised. The availability of pure antigen will enable more specific antisera to be produced in the future. Nematodes have been identified as pests ofwhite clover, but little published information exists on their distribution or range ofhost plants in hili country. Information was needed before priorities could be set in the breeding programme for a more persistent and pro ductive white clover cultivar in summer-dry hili country. A survey of the distribution of root knot and clover cyst nematodes was undertaken in this important class of land. White clover populations at 62 sites were sampled and the plants taken to Palmerston North for analysis. Soil shaken from roots was combined for each site, sieved, and stirred. Half the soil was potted and sown with tomatoes to trap root knot nematode, and the other half was washed to extract cysts of clover cyst nematode. Twenty-eight of the 37 North Island sites and none ofthe 25 South Island sites had root knot, whereas 31 North Island and 14 South Island sites had clover cystnematodes in sampies. The survey has shown that both root knot and clover cyst nematodes are widespread in North Island dry hili country, and any white clover bred for this area should be resistant or tolerant to both nematodes. However, if a separate regional selection is required for South Island dry hili and high country, then it is probably necessary to consider only clover cyst nematode. soil, the force needed to break up crumbs of soil, and the force needed to push a rod into the soil. The results from these measurements showed that the physical properties of the soil at the stripped sites were less suitable for plant growth than at the unstripped site. The site with the lowest pasture cover had the least desirable physical properties. The deterioration of soil physical properties at the stripped sites were partially caused by compaction of the soil during the stripping operations. This study highlights the need for consideration of the physical properties of soil in any land restoration.