Dr John Kirkegaard has been at the forefront of the conservation agriculture revolution that has transformed Australian farming over the last three decades. With food security becoming an ever more pressing issue, his research is helping farmers around the world become more productive as well as more environmentally sustainable.
With the polite efficiency of those used to being queried about a famous surname, Dr John Kirkegaard explains that, yes, he has looked into it but, no, he doesn’t appear to be related to the famous Christian existentialist philosopher.
Kirkegaard (which means ‘church garden’ in Danish), is a particularly appropriate patronymic for one of Australia’s pre-eminent crop agronomists, explains the Senior Principal Research Scientist and Group Leader of Innovations for Sustainable Farming at the Division of Plant Industry at CSIRO, Australia’s national science agency.
“The next revolution is going to be about efficiency, about breeding new varieties and managing the environment they grow in well.”
“My great-grandfather immigrated to Australia. He ended up owning a farm in Queensland’s Darling Downs and was a founding member of Queensland’s wheat board. My grandfather had an agricultural machinery business.”
At 13, Kirkegaard enrolled at Nambour State High School, which has since become famous for producing a range of high achievers including Australia’s former Prime Minister, Kevin Rudd, and its current Deputy Prime Minister and Treasurer, Wayne Swan, but which back then appealed to the outdoorsy country boy because it had a farm students could work on.
In the 1980s, the period in which Kirkegaard was studying at the University of Queensland, Australian agriculture was in a state of crisis. Massive amounts of topsoil were being lost to wind and water erosion and fears were mounting that traditional farming practices, developed for European conditions, were ill-suited to Australian conditions. Conservation agriculture, a minimalist approach to farming that first emerged in the US during the dustbowl era of the 1930s, was gaining traction among many of those involved in Australian agriculture. Kirkegaard was an eager convert to the cause but was determined to maintain a pragmatic and scientific approach.
Kirkegaard explains that the conservation agriculture movement promotes three elements: good crop rotation, no tillage and protecting soil by leaving residue on it.
“Those are all sensible principles but I was also happy to consider other ways of using inputs efficiently, such as sowing at the right time and implementing systems to conserve water in the soil. And, unlike some others, I was prepared to acknowledge and investigate conservation agriculture’s shortfalls.
“After over a century of working cultivated soft soils, I didn’t believe farmers could move into uncultivated soils without problems. And there certainly were issues. I focused on understanding what was causing those issues and trying to find solutions.”
Kirkegaard has now spent nearly three decades helping fine-tune conservation agriculture systems and identifies three main areas he’s focused on during that time.
“Firstly, if you want to grow crops year after year without taking residue away you have to have a good rotation, otherwise you just accumulate diseases. When I started my career in the 1990s, a disease-resistant strain of canola was being promoted as a good rotation crop. My colleagues and I spent a lot of time looking at how wheat rotated with canola compared to other options, such as lupins, peas or other common legumes. It became apparent that wheat grew much better after a canola crop but no one knew why.
“We investigated a possible process that I called ‘biofumigation’; there were chemicals in the roots of the canola plant that were improving the soil biology. While farmers didn’t make much money from canola, it was found that by rotating wheat and canola they ended up making 30 per cent more profit, largely because the post-canola wheat crop yielded so much more.”
At the start of the 1990s there was almost no canola being grown in Australia but by the end of the decade it was covering 2 million hectares and it’s still the most important rotation crop in Australia.
“The second thing I looked into was why wheat was growing 30 per cent slower in fields that hadn’t been tilled. Along with postdoctoral fellows, we discovered that when the roots’ growth slowed due to the hard soil, the bacteria that exists around root tips, feeding off their sugars, builds up, which creates inhibitory chemicals that slow the growth of the plant.
“So that was a 30-year mystery solved and out of that research came a lot of work showing that wheat varieties with faster-growing roots did better in no-till fields. It also made it clear that the problem could be mitigated if farmers planted earlier, when it was warmer, or used deeper sowing tines to loosen soil immediately below the seed – both allow the roots to grow quickly to escape the inhibitory organisms.
“The third area, and the one I’m working on now, is effective water conservation. Often farmers capture water and keep it in the soil but plants aren’t using that water, particularly the water in the subsoil. If a crop dies of water stress and you’re finding water in the soil that should have been available to it, that means there are subsoil constraints getting in the way. I’m currently researching those constraints and there are some exciting findings. That work has made it clear to farmers that every millimetre of water they can capture in the soil and get their crop to use is extremely valuable.”
Kirkegaard has been a pivotal figure in the conservation agriculture revolution that’s transformed Australian farming over the last three decades. And it’s a revolution that, if exported to the rest of the world, could delay or prevent the widespread starvation and social instability Malthusians have long worried will result from exponential population growth.
“Although other countries, notably the US and Brazil, embraced this earlier, Australia has taken it up more enthusiastically and is now the world leader. In the dry soil, mixed farming zones in western and northern Australia there’s now close to 100 per cent adoption of conservation agriculture and 78 per cent of the nation’s arable land is now farmed this way,” Kirkegaard notes.
Farmers and agricultural scientists throughout the world have expressed a keen interest in the work Kirkegaard and his colleagues have done and it’s conceivable that in years to come the export of Australian knowledge about sustainable farming systems will be even more important than exports of its agricultural produce in helping to prevent the kind of food riots that occurred in 2007–2008.
“I’m cautiously optimistic about the future,” says Kirkegaard. “We’ve continued to get two per cent annual yield improvement in crops in Australia for the last three decades, while moving to more sustainable practices. Enormous increases in agricultural productivity around the world can be achieved from doing relatively straightforward things.
“We’re not going to have another input-driven green revolution – we’re not going to discover something like nitrogen fertiliser again – so the next revolution is going to be about efficiency, about breeding new varieties and managing the environment they grow in well. Of course, climate change is going to have an impact on the availability of water, land and input prices and that just makes it more important that we manage those resources well.
“If you look at who is citing my research, people in countries such as Canada and the US are very interested. Even in Europe, where there’s been little take-up of conservation agriculture, there was a lot of attention given to using canola as a rotation crop. People in the Middle East are now trying to apply the things that have worked in Australia and I’m currently involved in a project in India looking at capturing deep soil water.”
Kirkegaard has recently returned to his ancestral roots, having been awarded a Velux Foundation Visiting Professorship at Copenhagen University. He is collaborating on root science research with Danish academics and is excited to be mentoring some postgraduate students during his stay, having long worried that popular misconceptions about farming are discouraging others from following in his footsteps.
“My biggest frustration is that we are not attracting the brightest young people into agricultural science because they’re simply not aware of all the exciting science going on in the field. There are farms where driverless tractors, guided by satellites, are navigating 2000-hectare paddocks, sowing to within 2cm accuracy. That’s not the future, that’s happening now. There’s little understanding that, far from being the traditionalists and even environmental vandals they’re sometimes made out to be, farmers are great innovators. I tell people what I do is ‘forensic agronomy’. I follow the best farmers around, look at what is working on their farm and try to understand why it is working. Some researchers are happy to be in a lab, but I’ve always wanted to be out in the field, both learning from farmers and communicating what I’ve learnt from my research back to them.”