From outer space - on Google maps - the difference is clear between two paddocks on the same alluvial flat in the Hastings Valley near Wauchope.
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The fence line between them divides light and dark with the latter supported by biologically active soil.
"The best things in life are free," property owner Jeremy Bradley said, who with his partner Cathy Eggert thoroughly tested the two adjacent paddocks to set a baseline of data after 10 years of regenerative work.
"Both paddocks get the same sunshine, rain and air. Soil health, regeneration and productivity depends on maximum retention of the free stuff. The sun and the rain provide the energy for photosynthesis and the air provides the nitrogen, oxygen and carbon needed for microbial activity."
One paddock has been ripped deeply with a Yeoman's plough and dosed with rock phosphate before being grazed rotationally.
"Taller pasture harvests more atmospheric carbon into the soil," he said.
This provides more food for the microbes and more root mass. After grazing, much of the plant root mass dies back. Dead roots then become carbon-rich compost deep into the soil, recycling nutrients like phosphorous that were delivered from far away by fungi with long tentacles known as hyphae.
The difference between the two paddocks during the drought was apparent but last week, in the middle of a wet winter, the contrast was again highlighted, after frost touched kikuyu in the other paddock but left this one alone because a nutrient dense plant has stronger cell structure.
Data proves analysis is right
Jeremy Bradley and his partner Cathy Eggert run Beechwood Biological Solutions and are best known for their dispute with the APVMA over the right to market a culture of native fungi to farmers for the control of invasive Parramatta grass.
Other local fungus have been cultivated in their on-farm laboratory and inoculated into the soil to deliver nutrients to plants while building soil structure. "Endophytic fungi live inside plant roots and trade eco-system services and products for carbon," Mr Bradley said.
Tests were carried out with the support of Soil C Quest, helped by Beechwood Biological Solutions and Rosewood Environmental Services with Australian Precision Agricultural Laboratories.
Two side-by-side test cores to a depth of one metre were taken from eight locations - four in each paddock - with comparative findings showing an additional 168 tonnes per hectare of CO2 equivalent. A test pit dug at the same time found fungi on roots to two metres.
"It was important to measure deeply because soil carbon in the top 300mm is in flux, cycling between plants and the atmosphere," Mr Bradley said. "At 1m and below that soil carbon is more permanent."
Soil carbon in the biological paddock showed levels of 2.5 per cent soil organic carbon compared to 1.9pc for the set-stocked paddock that had occasional applications of super phosphate and lime.
More relevant to East Coast graziers dealing with acid subsoils, is the fact that pH in the biological paddock was closer to neutral throughout the entire profile. When pH is low, toxic aluminium and iron are soluble. At higher pH these toxic elements are no longer soluble while other nutrients become available.
Greater levels of humus in the biological soil not only act as a pH buffer but allow greater exchange of cations. Increased cation availability improved the transfer of calcium and magnesium.
With greater porosity, and less compaction and toxicity in the deeper soil layers, plants roots were able to penetrate to greater depth where they could mine nutrients that might otherwise have been lost.
During the peak of the drought when measurements were taken, tests showed 20pc greater soil moisture.
"Air is around 80pc nitrogen," Ms Eggert said. "When you increase carbon content you get more air into the soil. That way microbes living in the soil and on legume roots can provide much of the Nitrogen needed by the pasture directly from that air."
In fact, the increase in nitrogen on the regenerating paddock compared to the control shows up on the data as having five times the amount of nitrogen in the form of nitrate which is more plant-available.
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