PEST WORK HELPED RAISE OUTPUT

Press, Volume CX, Issue 32459, 20 November 1970, Page 10

PEST WORK HELPED RAISE OUTPUT

A scientist whose work on the grass grub and porina caterpillar problem in Canterbury in the last 25 years has contributed to a notable upsurge in farm output will retire on December 16. He is Mr J. M. Kelsey, officer-in-charge of the Lincoln sub-station of the Entomology Division of the Department of Scientific and Industrial Research.

The experimental work with which Mr Kelsey was associated in Mid-Canterbury in the late 1940 s pointed to the pre-eminence of D.D.T. as a means of economically controlling both grass grub and porina.

This week, he recalled how land carrying less than two ewe equivalents to the acre had blossomed after treatment with D.D.T. to carry up to seven or eight ewes to the acre. One farmer on light land in MidCanterbury told him that D.D.T. had been responsible for lifting his stock carrying by at least 500 per cent and possibly by nearer 800 per cent. And on a property of 3700 odd acres in an area with a carrying capacity of about a ewe and a half to the acre pre-D.D.T., he recalls that after treatment 425 two-year bullocks and 26,000 sheep were carried one winter and there was still surplus feed when other properties were still suffering from grass grub and porina damage. Unhappily because of residue problems in soils, plants and animal products, D.D.T. has become almost a dirty word these days. Mr Kelsey, however, holds firmly to the view that it is one of the safest insecticides that there has been and that there is no sound scientific reason for the present restriction of its use. It is his belief that in 15 or 20 years time it will again be used on a world-wide basis for the benefit of mankind. Mr Kelsey has spent 40 years working on entomological problems, if four years at university are included. Bom in Auckland in 1907 and the son of a farmer at Glenafton in. the Waikato, Mr Kelsey attended Auckland Grammar School until illness interrupted his studies in his second year. When he recovered he worked on farms for about 15s a week until he met Dr D. Miller, director of the entomology department of the Cawthron Institute, at his uncle’s orchard at Henderson. Dr Miller indicated that there could be an opening for the young man in his department and encouraged by his uncle, who introduced him to the professor of zoology at Auckland University, Mr Kelsey began what amounted to an orientation course at the university to master such skills as using a microscope. He realised then that if he was ever to take up studies at the university he would have to write much faster to keep pace with the lecturers, so he also took a course in shorthand and typing at the Auckland Business College that-was soon to be of great value to him. In January, 1931, he Joined the entomology department at the Cawthron Institute as an entomological assistant Only nine months later the country was in the throes of the slump and not

only were salaries cut back but there had to be a retrenchment in staff. As the most recent recruit on the staff Mr Kelsey should have lost his job but because of his training in typing and shorthand ne was kept on to do clerical work as well as perform the duties of a technician. The former work also gave him a valuable insight into what other members of the staff were doing. By early 1937 he had saved enough money to embark on a university course and so he resigned from the institute and spent the next four years at Auckland University, starting his course with provisional matriculation dependent on his passing at least two subjects in his first year. In 1940 he completed a bachelor of science degree and at the beginning of 1941 joined the Department of Scientific and Industrial Research. His interest in entomology had been maintained during his university course in that in the long vacations he worked for the State Advances organisation making property inspections for boring insects and termites. When he joined the department his work, was mainly in the Auckland area and in New Plymouth on termites—looking into the number of species involved and their spread and the biology and ecology of the pests. In 1945 he was transferred to Ashburton to take charge of a new substation to work on the grass grub problem. This sub-station was established as a result of the efforts of the then secretary of the D.S.I.R, Mr F. R. Callaghan, and Mr L. J. Dumbleton, who will also shortly retire from the department Mr Kelsey remembers that his first visit to Ashburton to size up the problem and select a site for the new station was at the time of the great snow of that year when the ground was covered to a depth of 15 inches and power and telephone wires were down everywhere. When he was leaving Ashburton for Christchurch 14 years later there was another snowfall of four inches. Mr J. M. Hoy also came to Ashburton to work with Mr Kelsey on the problem and today, as Dr Hoy, he is director of the Entomology Division. Mr Kelsey remembers that in their early trials they tried everything that might offer some possibility of exercising control, including lead arsenate, which was then used on tennis lawns and bowling greens at the rate of 4361 b to the acre and at a cost of more than £72 an acre. Trials were laid down in areas including Ealing, Carew, Seafield, Newlands and Winchmore, and Mr Kelsey recalls that by March, 1947, D.D.T. and lindane were showing distinct promise. Mr Kelsey says that they were fortunate in starting their work at a time when

D.D.T. was becoming popular throughout the world. It had played a leading part in the war in keeping the armies healthy as a result of the deiousing of local populations and then of the troops. He said that when some of the local people in some of the Eastern countries had been treated with D.D.T. preparations they had suddenly found they no longer needed to scratch themselves and after years of scratching were at loss to know what to do with their hands. D.D.T., too, played a conspicuous part in the campaign against malaria in the countries where the war was being fought. Mr Kelsey said that their work showed that fine dust formulations worked better than coarser ones and it was also found that D.D.T. was effective for two to three years against both' grass grub and porina whereas lindane had to be used annually.' The work was extended to the North Island as well as the South, but Mr Kelsey said that in areas where the soils contained more organic matter and where due to climatic conditions there was almost continuous growth the response to treatment was less marked than in Canterbury. Responses were even less on the better Wakanui soils with more organic matter and better moisture holding qualities than on Lismore stony silt loam. The scientists put out their first recommendations about the use Of D.D.T. and lindane in 1950 and then for the next 10 to 15 years revised their recommendations from time to time. • Mr Kelsey has understandably been saddened by the demise of D.D.T. He says that the theory now is that nothing should be used that has a long residual effect so now materials were being used that had short residues but which were very much more toxic, and his view is that society will ultimately pay for this in upsetting the normal processes of soil organisms. He says that it may be possible to short circuit or do without the nitrogen cycle by use of ammonium sulphate or liquid nitrogen, but he was old fashioned enough to want to see the old processes continued in the belief that these must not be interfered with or the soil, plant, animal relationship upset. They had done enough* work to show that in Lismore stony silt loam there were dangers involved in upsetting the soil structure. The organophosphate insecticides now being used tended to kill an infinitely wider range of organisms than D.D.T. ever did. D.D.T., he said, had an effect on certain organisms and for instance where it was used excessively earth worms would stop casting and there had been the case in the United States where robins had died after eating worms from an area treated with D.D.T., but the treatment in this case had amounted to between about 901 b and 1201 b of D.D.T- to the acre. Mr Kelsey said that in the second year after D.D.T. treatment earth worm numbers actually began to increase again because of the increased pasture growth and greater return of organic matter. While believing that D.D.T. will come back into

use again on a world basis in the next 15 to 20 years, Mr Kelsey said that New Zealand had no alternative but to prohibit the use of the material when it wished to trade with the United States and that country would not accept'products with D.D.T. residues.

But it was ironical that the decisions about D.D.T. were not scientifically based but made by conservationist and ecologist type people and by population hysteria pressure.

Such authorities as Weyland Hayes in the United States and J. M. Barnes in Britain, who held positions equivalent to Director General of Health, both considered that D.D.T. was one of the safest materials ever used and that such rela- ' tively low residues as were found in human foods were safe. The World Health and the Food and Agriculture Organisation also maintained that they would continue to use D.D.T. where it Was justified and so long-as it gave good results. Mr Kelsey foresees the two pests still being with farmers for some time to come yet, but with the insecticide attack changing from time to time. Mr Kelsey has submitted for publication or had published a total of 81 papers. Many of these have been in the field of applied entomology and on the revision of grass grub control procedures. In his retirement he will live at Orua Bay, near the heads of Manukau Harbour, which has no road access. He first visited the bay when he camped there in 1916. Thirty-three years ago he bought a half acre of swamp for £32. Over the years it has been drained and since 1963 he has had a house on the site.