Different forms and rates of sulphur (S) fertiliser were examined for developing oversown tussock in sunny-lying South Island high country. Sulphur significantly increased dry matter (DM) production (p = 0.0001). Soluble forms of S were most effective in the first year, and lasted 15-18 months. Sulphur bentonite prills took 6 months to be effective, but over time the higher rate (56 kg S/ha) was one of the better treatments. Elemental S on its own was ineffective even after 3 years. The combination of soluble sulphate and finely divided elemental S (56 kg S/ha as sulphur super extra) was the most effective treatment. In the first 2 years alsike clover was the most dominant pasture species. Native grasses became dominant in the third year. After retopdressing at the beginning of year 4, pasture production again improved, particularly in those treatments containing only soluble forms of S. White clover was the dominant pasture species in the fourth year. Sulphur significantly increased soil-available nitrogen levels (p = 0.0001). Keywords development, sunny hill country, sulphate sulphur, elemental sulphur, sulphur super extra, sulphur bentonite prills, available nitrogen

A survey of the mineral composition of 6 swede and 3 kale crops from 9 farms near Gore, Southland, New Zealand, showed that while they provided adequate concentrations of the macroelements and Fe to meet dietary requirements of livestock, the kales were deficient in Mn and Zn (stems only), Cu, Co, and I, whereas the swedes were deficient in Mn, Zn, Se, and I (bulbs only), Cu, and Co. The applications of Co-, Se-, and Cuamended fertilisers at sowing and as a topdressing had no significant effect on the Co and Cu concentrations of swedes and kale. The Se concentrations in the leaves of the kale were roughly doubled 2 to 4 months after the topdressing with Se-amended fertiliser.

Since 1994 Ravensdown have carried out a series of pastoral trials in South Canterbury, aimed at looking at the relative effectiveness of different forms of nitrogen in the spring. These trials showed that in general those N products containing some nitrate-N (i.e., calcium ammonium nitrate - CAN, and ammonium sulphate nitrate - ASN) could be more effective than urea and ammonium sulphate when soil temperatures were low. However, responses were inconsistent because of spring climatic conditions. In 1994 and 1996 CAN produced the most dry matter but in 1995, responses to the form of N were less clear. Responses to nitrate-N were generally best when spring soil temperatures were 3-5°C at the time of application. The magnitude of N responses varied with the rate applied, and the type of pasture to which N was applied. Responses generally lasted the equivalent of two to three grazings. Keywords: ammonium-N, ammonium sulphate, ammonium sulphate nitrate, calcium ammonium nitrate, nitrate fertilisers, nitrate-N, urea

Sulphur trials were carried out in the hill and high country of the South Island from 1986/87 to 2000/01. Initial trials showed that sulphur fortified superphosphate fertilisers are more effective products than fine elemental sulphur and sulphur bentonite prills, both in terms of dry matter production and cost effectiveness. This is because Sulphur Super products contain sulphate sulphur and finer elemental sulphur. Sulphur Super Extra (28% S) was more effective in the short to medium term than Maxi Sulphur Super (50% S) largely because it contained more sulphate sulphur. It would be a more preferable option for development, particularly when used at above maintenance rates. It is preferable to apply these products on a biennial rather than a triennial basis to maximise dry matter, maintain better sward composition and to improve the chances of coinciding application with better growth conditions, most notably summer rainfall. Residual elemental sulphur oxidises with time, reducing the dependence on biennial application, although there is still a risk of temporary sulphur deficiency and a delay in response of clover to follow up topdressing if topdressing is left beyond 2 years. Herbage sulphur levels, in conjunction with observation of pasture composition and vigour are useful to indicate when sulphur fertiliser needs to be reapplied. Keywords: sulphate sulphur, elemental sulphur, sulphur bentonite prills, wet mix Sulphur Super, Maxi Sulphur Super, anaerobic nitrogen

In the period 1988-96