THE Northern Rivers cattle property Tancredi is the scene of a remarkable uplift in productivity following a major pasture rejuvenation project based on deep-level contour ploughing.
Kevin Ellevsen his son Nigel and Kevin’s brother Raymond have embarked on an ambitious program to rehabilitate severely compacted pug clay soils to maximise effective rainfall, minimise run-off and make leached minerals available to the root zone.
Tancredi is 430-hectares of picturesque undulating coastal country along Boomi Creek near Woodenbong at the headwaters of the Clarence River. It is also the home of the Ellevesen’s 200-cow Ideal Santa Gertrudis stud.
Mr Ellevsen said the severe compaction was the result of years of grazing the water-shedding pug clay soils. An impervious hard pan had formed only 2-3cm below the soil surface preventing both water and root penetration.
The Ellevsens have drawn on the knowledge of PA Yeomans and some of the thinking of landscapes guru Peter Andrews.
“That clay barrier had cut our effective rainfall by at least 50 per cent,” Mr Ellevsen said.
“The ground was either drying out very quickly or leaving swamp like areas of water. Either way the pasture was not responding even after the best rain.
“We were always saying ‘if it would only rain a bit more we would get some good pasture growth’. But what we were failing to understand was the excellent rain we were receiving was running straight across the paddocks and down the creeks.
“It was never about getting more rain. It was always about finding away to make capturing and making better use of the rain that fell.
“In a nutshell that doing exactly what Yeomans said all those years ago and getting the rain into the ground.”
The Ellevsen’s brought in experienced local contractor Michael Smith from MJ Smith Ground Preparation at Woodenbong, who used his the Yeoman plough behind a Caterpillar grader.
The deep ripping at 30-50cm and shattering of the soil profile between each rip delivered two main benefits. The first was it broke through the pan causing the subsequent clay slabs to break down. Secondly the action of the shank brought up to the root zone important minerals that had been leached down through the soil profile.
The ploughed areas are currently nothing short of spectacular. In those areas the now luxuriant pastures include species that have either never been seen or at least not seen in decades.
In contrast the areas still to be renovated continue to produce pasture that is clearly struggling and in competition with a significant weed burden.
“At $60/acre for the contour ploughing and $10/acre for an over-harrowing it was a very budget friendly exercise given the increase in productivity and other associated benefits," Mr Ellevsen said.
“We’re looking at a five year and possibly even more than a 10 year interval before we need to treat this country again.”
The Ellevsens also worked through the Soil Foodweb International at the Southern Cross University at Lismore and enlisted the help of internationally recognised soil microbiologist Dr Elaine Ingham.
“That opened the door on a whole new world of knowledge,” Mr Ellevsen said
“We learnt about the role of fungi and the importance of microbial herds and essentially why our soils and and pastures were so run down.”
Mr Ellevsen did not have to go far to find PA Yeoman’s guidance.
“His book on keyline farming was actually a favourite of my fathers and had been sitting in the library for years,” he said.
“The hardest part was blowing the dust off it. Reading and understanding it was easy. Even after all these years the logic of what he says about soils, water flows and pastures and how they can all be managed with contour ploughing just jump off the pages.
“We must be slow learners,” Mr Ellevsen laughed. “We’re had this problem for 60 years and finally we found the solution had been with us the entire time.”