GRASSLAND FARMING

Bay of Plenty Beacon, Volume 11, Issue 77, 8 September 1947, Page 6

GRASSLAND FARMING

ABSORBING Y.F.C. LECTURE PLOUGHING AND RESOWING ADVOCATED A crowd in the vicinity of 150 farmers and Y.F.C. members attended a lecture in the Awakeri Hall on Wednesday night. The speakers were Messrs Bruce Levy and Peter Sears of the Grasslands Division, Department of Scientific and Industrial Research, Palmerston North, and their subject was “Intensive Grassland Farming.” The speakers were welcomed by Mr J. Barr, District Chairman of the Y.F.C. and were thanked by him for their address at the conclusion of the evening. The two took turns in addressing the meeting and the lecture was illustrated by means of lantern slides. At the conclusion of the address Mr Levy invited®questions and was met with an excellent response. - The text of the address is as follows:

Intensive grassland farming is no idle dream nor can we condone the many failures and short-comings today, to appreciate and to strive for the enormous potentialities latent in our climate the greatest and most favourable grassland climate in the world.

It and it alone enables our grassland farmers to produce animal products at approximately 1/3 the effort of our overseas competitors. What a wealth of stock feed we could produce did we but take grassland farming up zealously and put into the business of growing grass all the energy and talents we possess and which are - necessary to grow this most astounding of crops. The world today is calling aloud for greater production: it is an era of vast opportunities to expand and to consolidate the one New Zealand industry that is really worth while. Some enthusiasts are showing the way and are making the soil produce as never before. Mr Sears and I would like to examine those methods of the high grassland producer and we hope to leave with you some figures and facts for comparison with what your own pastures and your pasture management is doing. Basic Principles The first basic principles are to grow clovers and to build up and maintain a high per acre stock carrying capacity: to feed Jhat stock to maximum capacity and to so graze —manage the sward that the maximum possible of feed is utilised by in situ and uniform grazing over the whole area in order that there is secured, a uniform distribution of animal residues—dung and urine—over the entire area of the paddock, and paddock by paddock over the entire area of the farm. Any increase in the number of adequately fed stock—not starved stock—carries with it sward improvement: any diminution of stock numbers brings with it sward deterioration. One has only to compare the home padocks on a farm with the back paddocks; the night paddocks with the day paddock, to appreciate the enormous potentialities of the farm if all the back paddocks even were as good as the night paddock, the holding paddock, or the home paddocks.

The vital question therefore is how to carry and maintain this high per acre stock concentration and how to convert the majority of growth by in situ grazing into animal products and animal residues. Compost School With regard to the latter we have in this country a strong compost school. We agree entirely with the tenets of that school just so long as we can use the animal to convert the green stuff it eats into compost —liquid and solid—: to harvest, digest and distribute that compost over the grassland with the minimum of loss and at the lowest possible expenditure of energy by the farmer. Where we have these conditions there is no country in the world so heavily composted at such little cost, as are the high producing, grazed pastures of New Zealand. That compost is the life-blood of the pasture but there is a vast difference between the economy of animal made compost as against the rotting down of ‘herbage. In the latter case the energy and heat of decomposition is lost to the atmosphere whereas that heat and energy can be used to work the animal: to make flesh, wool and milk and to convert the residue into animal compost within some 24 hours of its being grazed. This quick turn-round of organic

and mineral ingredients is based on renewed growths and to high grassland production. At the Grasslands Division research into the part played by the animal in soil fertility building has been conducted by Mr Sears. In these trials measurements were made of the amount of pasture consumed by the animal and also the amounts of dung and urine excreted by the animal—dry sheep being used—together with chemical analyses of these excreta to determine the amounts of manurial ingredients that were returned to the soil. The pastures on which the trial was conducted were high producing and gave, on the full dung and urine return paddocks, a dry matter yield of 13,6751 b. per acre per annum. All this feed was consumed by in situ grazing and there was returned per acTe approximately 8 tons of dung and 14 tons of urine. In these quantities of dung and urine there were returned to the soil, nitrogen equivalent to that contained in 19.8cwts. of sulphate of ammonia: Potash equivalent to that of 16.6cwts. 30 per cent, of Potash Salts; Phosphate equivalent to 6.4cwts. superphosphate and lime equivalent to 2.4 cwts. carbonate of lime. Clovers Where a sward is composed wholly of grasses and non-legumes added lime and phosphate will not significantly raise production as growth will be limited primarily by the nitrogen supply that is dependent in the case of the non legume pasture on the action of free living soil bacteria (Agotobacter etc.) only. In a sward where there is good clover the nitrogen supplied by the free living soil bacteria is completely overshadowed by that fixed by symbiotic clover bacteria. Phosphate and lime are known to be the limiting factors for growth of clovers and the adequate supply of these by topdressing stimulates the clover growth. This added growth of clover means greater synthesis of carbohydrates. The clover taps the energy of the sunlight and uses this energy to combine particles of carbon, hydrogen and oxygen—ail from the air or from water —to form starches, sugars and fats that provide firstly for the energy of the symbiotic bacteria to live and proliferate and in the course of so doing to fix atmospheric nitrogen that makes extra clover growth directly possible and provides also some excess nitrogen that is exuded into the soil from the clover root nodules or in the decay of those nodules. Secondly these starches, sugars and fats in the foliage of the clover plant provide energy for the grazing animals to generate heat and motion to enable the animal to collect, mastigate and digest the feed it consumes: to convert that feed into flesh, milk etc. and to void its vast residues back on to the land. Of those stock residues nitrogen is of vast importance for- this substance in the life blood of the grasses of the sward. This results in a balance between grass and clover which we know is the desirable combination, both for production and for animal thrift. Clover dominant pastures are prone to induce bloat and feed flavours in dairy products and while there seems but little hope of building' towards the grass dominance without the intermediate clovery phase, and with our pedigree white clover there is need to warn against bloat particularly, yet the end pasture resulting where grasses asociate well with the clovers, give hope of greater per acre productivity of herbage with an increased per acre butterfat yield of a higher quality product. Feed Flavours During the 1934-36 investigatory period into feed flavours in cream throughout the Waikato, fit was clearly determined that clover dominant pastures gave rise to intense feed flavours and that the lower producing annual clovers, those which represent the early phases of pasture building in the Waikato and North Auckland more particularly, are worse in this respect than the higher producing types of clovers that figure in the ultimate highly improved and more grassy swards.

There is no doubt that in all grassland, nitrogen is essential to grass growth and the fundamental principles behind any pasture improverient work whereby grass dominance replaces clover dominance lies in one way or another in getting more nitrogen on to the country to become effective in September, October and November when the feed flavour intensity is most pronounced. To effect* this good strains of rye grass particularly must be used. (To be continued)