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

The effect of fine slurried lime applied at 200 kg/ha on soil pH at two depths was compared with 400 and 2500 kg/ha of local agricultural (ag) lime in the presence and absence of sulphur (S) superphosphate 20, in Marlborough hill country for one year. In the absence of fertiliser all lime treatments significantly raised soil pH in the top 25 mm for the 355 days after application. Initial responses declined from day 14 or 35 to day 138 before increasing at day 355. Fine lime did not significantly alter pH in the 25-75 mm zone until day 355. The low rate of ag lime significantly raised pH in the 25-75 mm zone for the whole year. The high rate of ag lime significantly increased pH in the top 25 mm over the other lime treatments for the 355 days and over the fine lime treatment in the 25-75 mm zone from day 35. In the presence of fertiliser in the top 25 mm, fine lime significantly increased pH at day 14 only, and low ag lime at day 355 only. The high rate of ag lime significantly increased pH over the control from day 14 and over the other lime rates from day 35. In the 25-75 mm zone the high rate of ag lime significantly increased pH over the control and the low ag lime rate from day 71 but was significantly better than fine lime from day 35. It is likely that rain immediately after application and higher than average annual rainfall hastened the release of fine and intermediate particles of lime. However provided lime meets the accepted criteria for particle size distribution and maximum size it is the rate of application which dictates the magnitude of response. In Marlborough hill country it was 43% cheaper to aerially apply 400 kg/ha of ag lime compared to 200 kg/ha of fine lime with the added benefit of a greater residual effect beyond one year. Keywords: agricultural lime, fine lime, slurry, soil pH

No abstract

The Co (Vitamin B12), Se, Cu and I status of livestock on 12 Wendon Valley farms was determined from the trace element concentrations of pasture, blood and liver samples collected in spring and autumn and comparing them to accepted trace element reference ranges established from earlier New Zealand-wide trace element supplementation trials recording animal responses. Both marginal Co and Se deficiencies in lambs were found on two farms while another three farms were marginally Co deficient, one farm was very Co deficient and a further two farms were marginally Se deficient. Iodine deficiency was observed in new-born lambs from ewes wintered on swedes, whereas the Cu status of all sheep was adequate. No Co deficiency was found in cattle but Se deficiency was observed on four farms. A marked depletion of liver Cu stores and Cu deficiency was found in all cattle and deer during the late winter/ early spring. Growth responses to Vitamin B12 and Se supplementation in lambs, and the absence of goitre in new-born lambs to I supplementation in ewes were also observed. The established diagnostic protocols based on pasture, blood and liver samples were shown to be effective in determining the trace element status of grazing livestock in the Wendon Valley. Keywords: blood, cattle, copper, deer, iodine, liver, pasture, selenium, sheep, vitamin B12