FERTILISERS

Bay of Plenty Beacon, Volume 4, Issue 308, 21 May 1941, Page 2

FERTILISERS

SUPERPHOSPHATE POSITION

POSSIBLE LINE OF ACTION

The importance ot fertilisers in New Zealand farming and the possible steps to meet a shortage, of superphosphates,, were discussed by Dr. M. Burns, of the staff of the Canterbury Agricultural College,Lincoln, in an address to the Geographical Society in Ghristchurch. The first shipment of fertilisers came to New Zealand in 1867-68, said Dr. Burn 1 :. This comprised island guanos. No other sort of fertilisers was imported until 1880, when bonedust was brought from Australia. Then,, in 1881, came the first shipments ol superphosphates, brought in by the first director of Lincoln College. He demonstrated the benefit of superphosphates. During the next ten years top-dressing had begun in the Waikato. In 1896 the New Zealand Government offered a reward; for the discovery of phosphates in the colony, nnd in 1902 deposits were found at Clarendon, thirty miles south of Dunedin. These were developed,, and the work opera Led until 1926, producing in that time 140,000 tons of fertiliser. They were then put out of operation by the compe/tition of cheaper phosphates from Nauru Island. Since then all New Zealand supplies had come from Nauru. Phosphate fertilisers had been responsible for. bringing into production in New Zealand thousands of acres of what Avere formerly submarginal scrub lands. They had made productive a large portion of the dairying lands of the North Island. What the. farmer had achieve °d in this respect offset much of the harm done in other places by Avrong use of the land. New Zealand used 100, COO tons of phosphate fertilisers a year, and of the 17,250,000 acres of sown grass land in the country a quarter Avas topdrcssed with phosphates. With the recent check on supplies from Nauru attention Avas being given to a of AA'hieh farmers had formerly taken little notice. This Avas the use of 25 per cent of serpentine rock Avith superphosphate to make silico-superprosphate. The use of this had the erect of retaining the effect of the phosphate in the soil for a lcnge.r time than AA'ith superphosphate alone. Dr. Burns then discussed steps New Zealand farmers might have to take to meet a shortage of superphosphate. The use of silico-super-phosphate avouM help. Tiiev' might lime heavily, and "sneak . along" without superphosphate, Avhich they would probably have to do. They might use the by-products of the freezing Avorks, but unfortunately most of these Avc-nt overseas, Avbcre there was a good demand, particularly from the cornfields of Queensland and the pineapple groAvers or Gawaii. The sources of supply for potash fertilisers Avere doubtful, and only small-stocks Avere in the. country. After a survey it had been found (hat there Avas not in Zealand any material AA'hieh could be turned *nto a reasonable supply of potash. The former high prices for butter and Avool could not be counted on after the Avar, said Dr Burns in conclusion. It be necessary to produce cheaply. That might be achieved Avith the help of a moratorium, or Avith A reduction of costs, A reduction could be achieved by loAAei Avages for farm workers, but that Avas certainly not desirable. It seemed that the lines of action might have to be by further use o/ mechanisation, and the more efficient use of more fertilisers.