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Four experimental releases of the parthenogenetic strain of Microctonus aethiopoides from Ireland were made in early 2006 in the Waikato Manawatu (two sites) and Hawkes Bay By early winter establishment was confirmed at all sites with parasitism levels exceeding 10 in the target host Sitona lepidus a serious pest of white clover in New Zealand Subsequent monitoring revealed considerable betweensite variation At the Hawkes Bay and Manawatu Feilding sites where overwintering weevil adults were still present in October over 30 parasitism was found in newly emerged weevils in December 2006 In contrast at the Waikato and Manawatu Bulls sites where there was no overlap of host generations parasitism was below detectable levels during spring and early summer but recovered subsequently The Irish M aethiopoides appears to have four generations a year and diapauses over winter as a first instar larva Following the initial success releases have commenced in other regions

The bacterium Serratia entomophila is a naturally occurring pathogen causing amber disease of the New Zealand grass grub (Costelytra zealandica) A novel granular formulation of S entomophila Bioshieldtrade; was applied to 18 pasture sites in a largescale programme to demonstrate efficacy against grass grub No significant difficulties were encountered in application of the granules through conventional machinery There were high populations of the applied bacteria in soil within the first week of application and within 6 weeks of application there was an average of 3 x 104 viable S entomophila of the applied strain per gram of soil This resulted in a significant (Plt;005) 20 increase in the incidence of amber disease in the treated grass grub populations compared to untreated populations Successful establishment of the bacteria in the soil and target population following Bioshieldtrade; granule application was demonstrated on a wide range of sites under various farming conditions

Livestock grazing ryegrass infected with endophytic fungi are susceptible to staggers, a neurological disorder characterised by uncoordinated movement and loss of appetite. A possible strategy to minimise staggers is to dilute the toxic effects of ryegrass by providing other non-toxic pasture species in the diet. Therefore, the incidence and severity of ryegrass staggers, and liveweight gain, was monitored in lambs grazing varying mixtures of ryegrass-cocksfoot pastures during four six-week periods throughout summer and autumn over two years. There was a significant effect of pasture type on staggers. On a scale of 0 (no staggers) to 5 (severe muscular tremors invariably resulting in collapse and tetanic spasm), pure ryegrass resulted in a mean of 3.1, S.E.M. + 1.6 compared with 0.3, S.E.M. + 0.9 with pure cocksfoot. Ryegrass/cocksfoot mixtures were slightly less toxic than pure ryegrass with means (+ S.E.M.) ranging from 2.2, S.E.M. + 1.6 to 2.9, S.E.M. + 1.8. Mean liveweight gains ranged from 62 g/d on both pure ryegrass and 80:20 ryegrass:cocksfoot mix, to 83 g/d on pure cocksfoot, with no significant effect of pasture type. In those periods when ryegrass staggers was significant, the percentage of ryegrass in the sward was positively related to the severity of staggers and negatively correlated with liveweight gain. The inclusion of cocksfoot in ryegrass-dominant pastures is thus able to reduce to some extent the adverse neurological effects of endophyte on lambs. Keywords: cocksfoot, endophyte, lambs, liveweight gain, ryegrass, ryegrass staggers

Production of summer forage is an important consideration in environments prone to extremes of heat or moisture stress. Tall fescue (Festuca arundinacea) and chicory (Cichorum intybus) are two forage species with the potential to overcome the production shortfalls of perennial ryegrass (Lolium perenne) in such environments. Trials from three New Zealand regions prone to summer drought (Taranaki, Hawke's Bay and Canterbury) were used to compare production of tall fescue and chicory with production from resident ryegrass. Consistent production advantages from tall fescue and chicory were evident in the two years after establishment. Potential production advantages can disappear in subsequent years when summer moisture levels are very high or very low, or temperatures extremely high. Moderate moisture levels in summer, indicated by moderate ryegrass production, gave the biggest relative summer production advantages to tall fescue. Keywords: chicory, dryland, forage production, ryegrass, tall fescue

Seedling and tiller core measurements on 60 paddocks sown in autumn 1991 on the East Coast of the North Island were made to monitor the success of new pastures based on drought-tolerant grasses. Pastures sown into cultivated seedbeds were generally more successful than direct-drilled pastures, having higher content of sown species and less competition from volunteer perennial grasses. In paddocks sown with mixtures of tall fescue and Grasslands Wana cocksfoot, cocksfoot was becoming the dominant,grass, except in areas of paddocks with poor drainage. Cocksfoot establishment in oversown pastures was good, but tall fescue in these paddocks declined to low levels 19 months after sowing. White clover was well established in all classes of pasture, despite relatively low initial seedling numbers in direct drilled and oversown paddocks. In contrast, red clover content declined, particularly in directdrilled and oversown paddocks. Keywords: Dactylis glomerata, direct drilling, Festuca arundinacea, pasture establishment, Phalaris aquatica, oversowing