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PASTURES THAT BEAT US

R 1. Hamiltoa*

There is widespread concern in Canadian agriculture about diversifi- cation from wheat and the ability of livestock production to expand to meet the market potential in North America. Increasing awareness of international competition is also becoming apparent, more specifically the ability of countries to produce beef at a lower cost than in North America. Fundamental to livestock production in many of these countries is pasture. This is an account of an Australian experience in the development of completely new subtropical and tropical pastures for beef production.

The story of the Division of Tropical Pastures begins with the federal research organization in Australia which is entitled the C.S.I.R.O. (Commonwealth Scientific and Industrial Research Organization). It is comprised of over 40 Divisions, has some 2,000 graduate scientists, and an annual operating budget of over $A.50,000,000. The C.S.I.R.O. is supported by both government and private industry. For example the Australian wool grower contributes a tariff from each bale of wool sold and grazier representatives sit on the research committees which adminis- ter these funds. Similar funds are received from the Australian meat and dairy producers and some other industries who are direct beneficiaries and for whom research is being conducted. Levies on produce are supple- mented by equal or larger Federal Government grants to provide sub- stantial sums for research for the wool, meat, and dairy and other indus- tries.

The Cunningham Laboratory, the headquarters of the Division of Tropical Pastures, was established in 1959, following smaller scale pasture research extending over the previous 25 years. Favourable long-term market conditions (deficiencies of supplies of home-grown beef) in countries with high standards of living (i.e. able to afford to purchase beef, such as North America and Europe) have encouraged a strong effort by the Australian Government to foster the expansion of beef production. This successful expansion in the Northern tropical zone was not possible for many years because of the poor quality of the natural grasslands.

Since the turn of the century, various plant scientists have surveyed the pastoral areas of northern Australia (Queensland, Northern Territory and Western Australia). The plant species available for livestock produc- tion were well adapted to survive the harsh climate and poor soils of these regions but did not provide good fodder in term5 of either yield or

' The author was a racarch scientist. Div. of Tropical P u m a . C.S.I.R.O.. Cunningham Lnboruoria. Brisbane. Australia, 1.966-1969. The position involved studies on the milk production potenrial of many new and relatively unknown tropical pvnue species. The experiences a~ the Cunningham Laborarorin form the basis of the observarions in chis uridc.

R. I. HAMILTON is Research Scientist, Forage, C.D.A. Research Station, Brandon, Manitoba.

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quality. Nevertheless, over seven million beef cattle (50% of population) are located in this sub-tropic and tropic area. Cyclical swings from drought to excessive moisture were a real threat to the stability of the grazing livestock industry.

One of the scientists who analyzed the situation and became associ- ated and charged with its development towards a more productive system was Dr. J. G. Davies, a Welshman, and a brother of Sir William Davies, former Director of the Grassland Research Institute, Hurley. In 1952, after establishing an international reputation in pasture research in south- em Australia, Dr. Davies moved to Brisbane. There h s first objective was to assess the problems associated with pasture improvement in the tropics. On the basis of his knowledge of outstanding work in New Zea- land, temperate Australia and Great Britain, he saw “the heart” of the issue as the development of effective legume-based pastures for a range of tropical environments. He considered that, for the initial phases of work, the greatest contribution could be made on the lands between the coast and the 20“ isohyet from northern New South Wales to the top of continental Australia.

Program All of Australia’s major field crop species have been introduced, and

the native flora has not contributed a single field crop to world agricul- ture. This fact provided an added stimulus to the sending of plant explora- tion teams to all parts of the tropic and sub-tropic world. Species, both legume and grass were collected in Central and South America, West and East Indies, and Central East Africa. Thousands of introductions have been made and evaluated in plant nurseries. The most promising have become the focal point of research of an interdisciplinary team. The successful outcome of this program has been the selection of a range of legumes and grasses from “wild” plants to form the basis of productive sown pastures.

Philosophy of Pasture Research Davies’ philosophy of pasture research was that a team of agrostolo-

gists, ably supported by groups working on the genetics, ecology, nutri- tion, chemistry, physiology and nutritive value of plants, and on legume bacteriology and soil fertility should be responsible for pasture investiga- tions in each of four major ecological regions. Established land use, and the natural vegetation provided the basis for a regional approach. The regions selected are the 10 million acres of self-mulching fertile clays in the “brigalow” region, two million acres of well watered but infertile sands in the coastal wallum region, five million acres of sub-tropical dairy lands, and 70 million acres of savannah country dominated by spear grass.

In addition to the 60 “plant” scientists of the Division of Tropical Pastures, different disciplines from other Divisions with C.S.I.R.O. (Soils, Animal Physiology, Mathematical Statistics and Computing Research)

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are located at the Cunningham Laboratory. The program is integrated and directed towards a single broad objective - the development of adapted and highly productive tropical pastures for northern Australia.

Development of Improved Pasture Legumes and Grasses

The development of new and improved tropical legumes has been achieved. Significant commercial areas of such plants as Townsville stylo (Stylosanthes humilk) and Siatro (Phaseolus atropurpureus) are com- mercially important. Other promising legumes (e.g. Desmolium intorturn, D . uncinatum, Glycine javanica, Indigofera spicata, Leucaena leucocepha- la, Medicago sativa) are presently in genetic and plant breeding programs at the laboratory. Commercial varieties of several of these are now be- coming available. The major obstacle to their extensive use both in Australia and internationally is the limited supply of seed and tremendous demand. Pasture grasses have also received attention and species such as Setria sphacelata and Sorghum almum are in plant breeding programs. Improved cukivars of many others, e.g. Chloris gayana, Panicum maxi- mum, Paspalurn sp., and Cenchrus ciliaris are available as the result of evaluating and testing plant introductions.

Scientific Achievements Associated with the development of these legume-based pastures have

been important scientific advances in fields such as legume bacteriology, plant bio-chemistry, nitrogen and mineral nultrition of plants and nutritive value of plants. A few examples are given.

Many of the introduced legumes were "poor doers" under the best of field and glasshouse conditions. Studies in legume bacteriology on the Rhizobium symbiosis found that the new species were highly strain speci- fic. Remarkable increases in yield and adaptation have been effected. The calcium requirement of Rhizobium was found Ito be very small, while mag- nesium was required in much larger quantities. Further work has led to radically different and fundamental hypotheses concerning the history of development and specialization in the Leguminosae.

Unfortunately, some of the more promising agronomic legumes were found to contain toxic substances. The ingestion of the legume shrub, Leucaena leucocephala, had produced depilation, abortion, reduced fer- tility and other harmful effects in humans, rats, mice, horses and sheep. Mimosine, an amino acid present in high quantities in Leucaena, was ex- tracted and purified. The purified amino acid was then conclusively shown to be the depilatory agent in sheep, as well as being lethal at high levels. Other studies at the laboratory have indicated the tremendous pos- sibilities of Leucaena which is one of the highest protein producing plants in the world ( I f tons of protein/acre/year). By management of the pas- ture to maintain a balance of 1egume:grass it is possible to avoid these syndromes in cattle, since the reaction of the ruminant depends on the level and method of feeding.

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Tangible Results Progress and tangible results have been realized by commercial

graziers in all regions. Generally it may be said that animals grazing un- improved native pasture require between four and seven years to reach market weight according to rainfall and soil fertility. Similarly, it would require between 10 and 100 acres or more to keep this animal alive. The standard liveweight curve for an animal involved liveweight increase in summer with loss in mid to late winter. Two steps forward and one back each year.

Improved pastures have removed the step backward and increased the carrying capacity to the range of two acres per beast to three beasts per acre in the more favoured climatic areas. The yearly liveweight curve does not feature a dip but a continuous gain with different degrees of slope. Liveweight gains per acre have increased as well.

The wallum area is a good example of the effectiveness of the pro- gram. This area comprises sandy mils and has 40”-80” of rain annually. Studies on plant nutrition revealed an amazing array of deficiencies and, for successful pasture establishment, the following initial fertilizer dressing was needed:-five cwt superphosphate, five cwt lime, one cwt potassium chloride, seven lb copper sulphate, seven lb zinc sulphate, and four oz of molybdenum per acre. Many of the grasses and legumes twted failed. Here in the sub-tropics, plants were required to survive the hot tropical summer and the cool dry winter with occasional frosts. A productive legume based pasture (Lotononis bainesii and Desmodium s p . ) has been developed, and liveweight gains of four and five hundred weight per acre at a stocking rate of one animal per acre has been achieved.

Here, when high rates of nitrogenous fertilizers are applied under these high rainfall conditions, outstanding results have been obtained. Liveweight gains of 12 cwt per acre per annum have been obtained, over a four year period on Digitaria decumbens (Pangola grass) with an input of 400 lb N/ac/year.

The demand for land is keen in the area as well as the other regions where the success stones have been similar, and a number of soundly based commercial enterprises are established.

Future Developments

Tropical pastures have been placed on a sound base and the labor- atory has established a considerable reputation in pasture research. Never- theless, this is the space age and the recent acquisition of a 24 channel emission spectrometer for the direct readout of essential and toxic elements in tropical legumes and grasses is an indication of the awareness of the sophisticated techniques required in modem research. Multi-element determinations with the instruments will assist a number of aspects of the Division’s research in plant chemistry, and plant and animal nutrition. Programs at the laboratory are continualIy being reviewed so that defi-

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ciencies in information which prevent progress can be made good. Team work and the interdisciplinary approach underly many programs.

It is apparent that there remains much work in many disciplines in this unique effort of developing completely new productive pastures. Yet the measures of success achieved in this short period are highly indicative of great leadership, determination and the use of science to achieve an objective.

Summary - Can Australia Compete?

Dr. E. M. Hutton, who became the second Chief of the Division of Tropical Pastures in 1969 made these comments in 1967, as the President of the Australian Institute of Agricultural Science: “The greatest potential for Australian agriculture is in beef expansion based on pasture. I hope we never get carried away by feed lots. I hope OUT American friends con- tinue their concentration on feed-lot produced beef. If they do we can undersell them on any market in the world”!

Dr. R. E. Wagner at the Forage Economics-Quality Symposium of the American Society of Agronomy in 1967 posed the following statement after a visit to Australia: Australia is determined to become a much greater force in the world beef markets - can the U.S. compete? Canada located much less favourably geographically might ask herself the same question.

In Canada, we are continuously evaluating our resources. Many re- cent studies have been undertaken to define the “most productive” soil and geographic resources whose agricultural use should be encouraged. Yet, we are a deficit beef producing country as is North America as a whole. It is imperative that we objectively tackle this problem head-on. This means not only a look at our resources, but the introduction of more efficient species into areas of “unproductive soil” and greatly expanded and increased productivity. If we are to compete, then a more concen- trated effort will be required-otherwise, those countries that make the effort will benefit.

References 1. Hurley, “Some Concepts and Methods in Sub-Tropical Pasture Research,” Comm.

Bur. Past. & Field Crops, Bull 47, 1964. 2. Hutton, E. M., “Integration of Northern and Southern Development as an Essen-

tial in Australia’s Future Prosperity,” J . Aust. Inst. Agric. Sci., 3 3 : 85-97, 1967. 3. Noms. D. O., “Legumes and the Rbizobium Symbiosis,” Emp. I . Exp. Agric..

4.Hegarty, M. P., and A. W. Pound, “Indospicine, A New Hepatotoxic Amino Acid from Indigofera Spicata,” Nature, Lond. 217 (5126): 3 5 6 5 5 , 1968.

5. Evans, T. R., “Factors Affecting Beef Production from Sub-Tropical Pastures in the Coastal Lowlands of South-East Queensland,” XIth Intern. Grassld. Coogr., In press, 1970.

6. Henzell, E. F., “Sources of Nitrogen for Queensland Pastures,” Tropical Grass- land 2: 1-17, 1968.

24: 247-270, 1956.