TOURING David and Mary Marsh's farm "Allendale", at Boorowa, is a rough experience.
It's September and cold when I first visit the Marshes. At this time of year, on the cusp of spring, much of the Central West is grazed as closely as a bowling green.
"Allendale", though, is a landscape lumpy with green-shooting grass tussocks. Riding over the farm on quad bikes with Mr Marsh is a body-rattling exercise as the bikes jostle over tussock mounds.
Counting the tussock grasses, Mr Marsh tells me, some of these paddocks host up to 59 species of plants in their pastures, including 15 natives. Fifteen years ago, many paddocks carried just one species: a cereal or oilseed crop.
Beneath the ground, over the same period, soil organic carbon levels have lifted from 1-1.6 per cent to more than 3.5pc. Above ground, at last count, 125 bird species inhabit the grasslands and the extensive patches of bushland the Marshes have planted.
These statistics seldom feature in any regular estimate of farm productivity: most would prefer to calculate "Allendale's" stocking rate - currently 620 breeding cows on 700 ha. Another 15pc of the property has been planted to bushland.
But the Marshes consider the seemingly irrelevant facts of biodiversity and birds as an indicator of success, on several fronts.
During the drought years of 2002-2010, much of the Central West/South West Slopes, and much of south-eastern Australia, accumulated debt.
"Allendale" didn't make much money over these parched years, Mr Marsh said, but it didn't lose it either.
He traded livestock to maintain the financial status quo, and invested in long-term capital works like fencing and new watering points.
Thanks to a near zero-input approach, there were none of the punitive costs that drove others to the banks.
If pastures ran down, stock got sold. No feed was brought in. "We adopted the attitude that growing plants and biodiversity were our business, and that meant we had to fall out of love with our animals," Mr Marsh said.
Rigorous feed budgeting ensured stock left the property months before feed levels got critical - and months before the livestock market dived on drought-induced panic selling.
Mr Marsh has only now fully restored the "livestock capital" depleted over these years. Stocking rates are now back to 11 DSE/ha. When he was pushing hard in a conventional system, Mr Marsh said, the property peaked at 12 DSE/ha.
Fertiliser and chemical haven't been part of "Allendale's" budget for 15 years.
Instead, production efficiency has been sustained through longer recovery times for pastures to capture an increasing share of free sunlight, while better using rainfall. Instead of fertilising to maintain a stocking rate, they stock to the carrying capacity of each season.
No inputs means no outgoings. "Allendale" once won district awards for the quality of it high-input crops. These days, the Marshes don't even own a tractor.
"We spend so little that it's a bit embarrassing," Mr Marsh said.
Energy is saved on another front: the half-hour that Mr Marsh spends moving cattle between paddocks is sometimes all the work he needs to do in a day. "I've had to get used to the idea of coming back to the house and reading a book," he said.
Extra time has meant extra thought on the ethics and philosophy of how people relate to the land, and more time to devote to the community.
The Marshes' minimal expenditure is a result of shifting responsibility for farm productivity from people to nature.
Or, as Mr Marsh puts it, "Instead of trying to bend nature to our will, we're trying to fit in with the way the world works".
Where they used to work to maintain a static "ideal" system using fertiliser and chemical, they now work to support biodiversity above and below ground.
Natural systems are always in flux. Modern agriculture attempts to minimise nature's changeability with technology to make production more reliable and consistent.
Instead of technology, the Marshes are employing biodiversity. In nature, the greater the level of biodiversity the more stable, productive and efficient the ecosystem.
Which is why Mr Marsh loves the growing numbers of bird species in the "Allendale" ecosystem.
"If a new species appears on the farm, I know that there must be a whole lot of other species underneath it to support it," he said.
"On the other hand, if I see the plant composition of a paddock simplifying, I know there must be something wrong."
David Marsh is a director of the not-for-profit Soils for Life
