Research Thinking With Eye On Costs

Press, Volume CIX, Issue 32303, 22 May 1970, Page 6

Research Thinking With Eye On Costs

According to Dr R. W. Brougham, in his presidential address to the thirtysecond conference of the New Zealand Grassland Association this week, farmers are being forced by current trends in incomes and prices to question all forms of advice —whether it be from farm advisory officers, private consultants, research workers, or university personnel—in economic terms.

Dr Brougham suggested that the agricultural research worker should be aware of this attitude, and at least a part of his research programme should be directed at areas of work that have application to farming as practised under the current and projected price structure. In this light, Dr Brougham looked at some examples of current research thinking and activity and attempted to assess their significance and likely implications for farming practice. For the last 20 years or so, he said, the value of ploughing up and re-sowing to improved pasture plants and crop species had been frequently questioned by farmers. Yet if they were to take full advantage of these improved varieties, and were to grow crops for out-of-season feed, then these pasture plants or crops must necessarily be incorporated into farming systems by use of the plough, or by various methods of oversowing or sod-seeding. Of the 22m acres that had been classified as cultivated land, less than 4 per cent had been sown to root or brassica crops or lucerne in 1967-68, and including lands sown to grass-clover mixtures the figure would be less than 6 per cent. These statistics indicated that on most farms pasture mixtures were sown, on average, to last for at least 15 years. ' There were about 120 m sheep equivalents on New Zealand farms in the same year, or three sheep equivalents for every acre farmed. Each acre would require about 30001 b of dry matter per year to feed these animals and, in fact, in large areas of the country yields in excess of 10,0001 b of dry matter per acre were readily obtained from these long-term pastures by sensible management that demanded the minimum of inputs. Costly ploughing and resowing were, therefore, being avoided by farmers at the expense of not incorporating the improved varieties into existing pastures. If farmers were to, be encouraged to use these varieties, more research was needed on improving and understanding the less costly methods of incorporating the varieties, such as over and under-sowing and sod-seeding. The same approach, Dr Brougham said, had been taken b/ the farmer to conservation practices. There was ample evidence throughout the world to indicate that dried grass or silage were better methods of conserving feed surpluses than hay making, particularly when considered in terms of feed quality and the prevention of losses in the conservation processes.

Yet the New Zealand farmer, in his assessments of these processes in economic terms, had come out in favour of hay-making. The factors determining this were the labour, building, and plant inputs required for feeding out silage and drying of grass respectively, and the very favourable drying climate that generally applied at hay-making time. The three methods of conservation had not been simultaneously evaluated at any research institution in the country. Before farming attitudes to these would be altered, studies at least in economic projections were needed. A parallel situation applied to the place fertiliser nitrogen had in New

Zealand farming. Evaluations of the place of this fertiliser in increasing productivity from grasslands had resulted in widespread use of this element in various forms, and in some countries where this had occurred the legume in pastures fixed quantities of nitrogen seldom in excess of 2001 b per acre per year. By applying elemental nitrogen of up to 5001 b per acre per year to grassland in these countries, marked increases in pasture productivity, had resulted and apparently net economic returns had increased. ' In New Zealand, however, because of a unique climate and a persistent and vigorous • growing white clover, elemental nitrogen was fixed by the legume component of rye-grass-clover pastures in quantities of up to 6001 b P ;r acre per year. The place of fertiliser nitrogen used in quantities similar to those already outlined was difficult to envisage here, particularly when considered in economic terms. Current work at the Grasslands Division supported this, in that the use of 4001 b of elemental nitrogen on a grass-clover pasture, with portions of nitrogen being

applied after each grazing in proportion to yield, lifted annual dry matter production by 40001 b above the 15,0001 b per acre per year obtained from a control treatment. At about 10c per lb of elemental nitrogen, the cost of producing 40001 b of additional dry matter was S4O.

If fully used by dairy animals—and current experience would suggest that this would not occur—the extra feed produced would have provided the feed for slightly less than half a milking cow per acre, or a gross profit of less than $5O an acre on current milk prices. When other inputs necessary to obtain this extra milk production were considered, the net returns from such an input would have been a negative quantity. This illustrated that at current dairying prices widespread use of fertiliser nitrogen On farms in New Zealand was simply not on. As an aid to producing out-of-season feed, however, in quantities much smaller than the example quoted, current work around the country indicated that the returns might be profitably increased, but these increases must not be at the expense of subsequent production levels because of a decline in white-clover yields. The cut-and-carry system of farming as developed to a high level of sophistication in the United States had also attracted attention in this country. Based on suggested rotations of maize and winter-growing annual ryegrasses, this system found favour from its exponents because of higher predicted annual yields of forage likely through the C 4 photosynthesis process of maize and similar crop plants. Recent evidence obtained in Holland suggested that crop plants possessing the reaction mentioned could maintain high rates of photosynthesis for short periods of up to three times those of temperate species. However, when growth was compared over longer periods, such as a growing season, the differences were markedly reduced A comparison of annual yields obtained from a cropping rotation of maize followed by Italian ryegrass with irrigated ryegrasswhite clover pasture at Palmerston North showed little difference, but major differences in the costs of a cut-and-carry operation to housed livestock compared with irrigation costs to permanent pasture could be easily computed. Non-irrigated pasture in the same environment frequently yielded 16,0001 b of dry matter to the acre. The difference between that yield and that of the maize and Italian ryegrass rotation was equivalent to the feed requirements of twothirds of a milking cow per acre, or $65 per acre. For the cut-and-carry system of farming to be profitable, the extra $65 per acre would need to cover costs such as cultivation and sowing of two crops per year, fertiliser inputs, capital expenditure and depreciation on buildings, storage and feeding systems, and cut-and-carry equipment. Most New Zealand farmers would need to see a careful evaluation of such a system, repeated over several years, and consistently shown to be profitable, before switching from their present lowcost farming operations based on the grass-legume pasture.