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Professor Ted Wolfe

Head, School of Agriculture, Charles Sturt University. Wagga Wagga. NSW 2678

In his opening address, Owen Whitaker (President, Grassland Society of NSW) referred to a loss of the link between good pastures and good cropping practice. On some farms, pastures have been relegated to the back paddocks or the forgotton corner. Under-investment in pasture is understandable, at least in grazing districts dependent on wool production (Table 1) but the rundown in investment threatens future production. Also, this Conference takes place against the backdrop of drought, not for the first time! (Figure 1).

It is therefore heartening to see the level of interest in the topic of pastures, indicated by the attendance of about 50 students and 100 professionals in agriculture at this Conference.

Table 1. Trends in Pasture Investment (Monaro)


Pasture improvement

($ invested per productive ha)

1988 1989 1990 1991 1992


Fertiliser 9.08 5.58 6.15 2.14 1.80


Seed sown 0.70 0.86 0.66 0.50 0.50


Source: Michael Boyce and Co., Chartered Accountants, Cooma

Figure 1. The 20-year NSW Drought Status

Dr Allan Wilson discussed pasture management in terms of biological control. Allan's definition of biological control involved the concept of the manager as a biologist, a person who understands the system and who strives to achieve stability, productivity and sustainability of the system. A good example of biological management is how a knowledge of the growth and development of target species can be used to manipulate the botanical composition of pastures. This sort of thinking will need to be applied to the management of herbicide resistant weeds.

Allan also reminded me that the best agricultural scientists are capable of working with nature, of uncovering nature's secrets, to develop sustainable systems. In this connection, I find it rather distressing that the latest issue of the Ansett Airlines magazine contains an article in which a person who is an enthusiastic promoter of permaculture is unfairly critical of agricultural science and scientists. I know something of permaculture, and I believe that scientific agriculture and permaculture are not poles apart. I do not unfairly criticise permaculture, and I am very suspicious of individuals who criticise me just because I have a University degree.

Michael Keys provided us with some good lessons from the Prime Pasture Program. That program places particular emphasis on the successful establishment of perennial pastures on the Tablelands and Slopes. The use of existing knowledge and techniques, such as minimising seed-set by weeds, selecting the correct type and timing of herbicide, and sowing with the correct design of seeding boot, has improved the success of minimum tillage/direct drill techniques to establish perennials like phalaris and cosksfoot in weedy pastures. To reinforce the message, Mike produced a satisfied customer in the form of Andrew Pickette of Bethungra. Andrew is now a convert to direct drilling, to phalaris, to Porto cocksfoot, and to the need to balance the sowing mix. Next time it appears, Andrew will measure the balansa clover component of his mixture in grams rather than kilograms.

Andrew also stimulated me to consider why tyned implements seem so much more successful than disc implements - I would like a physicist to explain this point to me one day. I believe that the chattering action of the tyne, compared with the smearing action of the disc, is the secret. Another point to emerge from Andrew's talk was the success of the partnership between commercial firms, farmers and district agronomists in ventures of this type.

Jim Shovelton outlined the concept of potential stock carrying capacity in relation to rainfall, and discussed how graziers might become quicker adopters of information so that their actual production moves nearer to the potential. Jim highlighted the Hamilton work undertaken by John Cayley and Jeff Saul which has shown that rates of greater than 10 kg phosphorus (P) per hectare and stocking rates of greater than 12 dry sheep equivalents per hectare are needed to optimise production of the sown pasture component and the production of wool per hectare. Indeed, the optimum P level on the Hamilton trial appears to be 20 kg P/ha - of course we must be careful not to apply these results too broadly, but this result (a suggested doubling of the recommended rate of P) is in stark contrast to the current practice on many farms over the last few years of low or nil applications of P.

There are now 25 groups involved in a Grassland Productivity Program which is checking the high P/high stocking rate system throughout southern Australia - we await these results with interest. This is another excellent example of grower participation in research.

Jim also produced Exhibit A - another satisfied customer in Ian Elder, who described with glee his results with a P rate of 25 kg/hectare. This rate has improved the perennial grass and clover components of his pasture and, according to him, has enabled an approximate doubling of stocking rate to 12 ewes per hectare. Ian has a different set of worries these days, compared with his financial problems of years ago. His main current worry is why his friends are not adopters!

Peter Cregan was the first to take up the running for pastures in the cropping zone. His definition of a pasture ley in 1984 stressed the fertility build-up and productivity of benefits from good pastures, and his 1994 definition now includes the important dimensions of water use, the reduction of salinity and acidity, and the effectiveness of good pastures in reducing crop diseases and weed numbers. He emphasised that poor pastures will create problems.

Peter made out a strong case for a perennial component and the perennial of choice for the southern wheat belt is lucerne. He then drew up a list of specifications for an ideal ley, such as ease of establishment, and persistence/stability (Allan Wilson). This specification will depend on the farm plan and the pasture crop rotation. For a long ley, a different mix of species and varieties will be used.

Peter praised the success of the National Subterranean Clover Improvement Program at a time when the body which administers the wool research levy, AWRAP, is considering reducing the funding of this vital program. It is paradoxical to terminate successful programs, and it is unfair to transfer the equity of funding subclover research from AWRAP to the Grains Research and Development Corporation, which is already putting up some of the research funds.

Barry Smith of Temora sang the praises of a perennial component in ley pastures, in this case both lucerne and cocksfoot with subterranean clover. Cocksfoot and lucerne can fight with one another, and a key to the success is the reduction in cocksfoot seeding rate to around 0.3-0.5 kg/ha. As Barry indicated, the presence of cocksfoot has some apparent advantages, by keeping out silvergrass and barley grass, for example.

Like all our farmer speakers, Barry spoke well and willingly - one of the great features of the Riverina Outlook Conference. In answer to his criticism of what I said at Temora recently, I repeat what I said then - lucerne is the best "grass" we have in the southern wheat belt and there are too many unanswered questions in my

mind to recommend confidently cocksfoot and phalaris west of the 500 mm rainfall isohyet. However, I do support the experimental thrust of both researchers and farmers in growing perennial grasses into the inland.

Dr John Leigh provided us with a highlight of the conference, the discovery of chemical compounds in phalaris, silvergrass and possibly other grasses, compounds which may adversely affect clover germination and growth in autumn. His talk raised the possible future need to manipulate residues of litter on the soil surface at the end of summer, implying a form of strategic grazing. Just as we think we know everything, along comes a new discovery which encourages us to re-evaluate how things should be done. As Ian Elder said to me "it is fascinating that straw has this effect - it explains so many things".

This leads me to the paper given by Dr David Kemp who returned us to the theme of Dr Allan Wilson's talk. If one understands the reaction of pastures to grazing management, it becomes possible to manipulate botanical composition in a manner that, in the long run, optimises stability, productivity, sustainability and profitability. However, the opportunities available in the variable Australian environment may be quite different from those which have been found satisfactory in "foreign" environments like New Zealand. We look forward to some conclusions and recommendations from David's research programs.

In summary, the organisers put togethr a very balanced program, and the speakers strongly supported the program with quality presentations. Even the unfortunate slide projector did not detract from the flow of new ideas which were presented. These ideas can be re-examined at a future date when each of you reads the Proceedings from this Conference. Suffice to say at this stage that there is a renewed interest in the role of pastures for animals, for soil fertility and for environmental stability, and there are plenty of new ideas.

One idea worth pursuing is the developing of key indicators which describe pastures in terms of attributes which can be measured - plant population, percent groundcover, biomass (yield), growth and botanical composition (Table 2). Work has started at Charles Sturt University to develop these critical pasture descriptors and I hope that eventually researchers and farmers will use them.

Table 2. Pasture-Top 10% (possible guidelines)


Seed pool >200 kg/ha


100% green cover by August 15


Spring peak of 3500 kg DM/ha at 10 sheep/ha


>50 kg green DM/ha/day from September 15-October 15


>90% legume in spring, before


cropping phase

Stocking Rate

15 DSE/ha

Livestock Production


Nitrogen fixation

70 kg N/ha/year

Crop production


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