Restoring deep rooted perennial grasses

He is most concerned about the degradation of the soil due to past livestock management decisions, leading to the loss of the native grasses in favour of shallow rooted exotic species, and the subsequent depletion of available soil carbon.

"In terms of soil carbon, I think it's important to understand that the CSIRO talks about Australian landscapes that have lost about 50pc of their soil carbon since white settlement," Mr Main said.

"And what that means is that soil carbon basically comes from microbes hosted by roots so there are less roots in the landscape now and that is because a lot of the deep rooted perennial grasses have gone because of our management practices during the past two hundred years.

"You can see that on Retreat."

Mr Main's brother George wrote in his book Heartland about the ecological history of the Dirnaseer area, describing its appearance prior to white settlement as open grassy woodland with an abundance of perennial native species.

"The soil used to hold the water when there was rain and the water wouldn't runoff so quickly because the soil acted like a sponge," Mr Main said.

"And when the sheep came to this district, their management wiped out all the native grasses and the country acted like it was in a drought even though there was good rainfall because that water wasn't being held anymore deep within the soil."

Mr Main said the long term damage done to the landscape can be seen through the drying of the swamps and the creek which used to flow persistently when the area was first surveyed.

"You look at the old parish maps and there are swamps on the property and they have all gone," he said.

"And the creek is now only an ephemeral stream after heavy rain."

As further evidence of the degradation of the landscape, Mr Main points to an old box tree from which bark for a canoe had been carved many years ago.

"There's that beautiful scar tree near the creek and you look at the creek now and wonder why there would be a scar tree nearby when there isn't any water in the creek or the swamp which was marked on the original survey maps," he said.

"And we think that's normal now, but it doesn't have to be like that.

"What I am trying to do on the place with soil carbon is get those perennial grasses back in the system, get the root volume back in the soil, so you have more soil carbon which is the microbes, but also greater water holding capacity.

"We are on the driest continent on earth, rainfall is getting more erratic, droughts are getting harder, so we want to be able to store as much water in the soil."

To increase the resilience of the family property, Mr Main ascribes to the evident success from North American landholder Gabe Brown has five soil health principles.

"They are the key for me to restore the health and resilience of my landscape," he said.

"It's minimizing the disturbance to the soil, increasing plant diversity, having a living root all year round in the soil, having one hundred percent ground cover one hundred percent of the time and then integrating animals into the system.

"Those steps are hugely important to build those root volumes and soil carbon."

For the future of his farming operation, Mr Main said increased soil carbon means increased water holding capacity, which leads to healthier plants and livestock.

"That feeds through to the animals, the animals are healthier producing better quality meat," he said.

"It's a real win/win situation for me and then the soil carbon project itself on top of the improved livestock enterprise is an extra form of income for the farm.

"We can benefit from these changes we are making through building soil carbon and not just from the production system year to year, day to day, but the longer term soil carbon as well."

Mr Main said lifting the level of soil carbon on his property is also critical to achieving carbon neutrality in the long term.

To work out his net position on emissions and carbon neutrality, he uses a leading emissions platform, Ruminati, to establish his base level and validate the work he is doing, establishing the deep rooted perennial grasses alongside an extensive tree planting program.

"My net emissions on the farm are 839 tonnes of carbon dioxide (CO2) equivalent per year," he said.

"If I can sequester enough carbon to increase my soil carbon levels by one percent over twenty five years to thirty centimeters, to a bit below or around the level of the carbon in the roadside beside the farm, that means 4263 tonnes of CO2 equivalent per year."

Mr Main said if he could sequester that much CO2 equivalent annually, he would have the equivalent of 2584 Australian Carbon Credit Units (ACCU) available for sale each year.

"I could sell all of those ACCU's and still be carbon negative," he said.

"So in my case, and only in my case, because everyone needs to know their own numbers, I'm still sequestering about 840 tonnes per year."