Co-sponsor Bryce Manderson, of Avoca Lime, said four seminars in the north each drew an average of 100 people including beef and dairy farmers, horticulturists and lifestyle block owners.
Barrett and Frew hammered the basic principles of regenerative agriculture: limited ground disturbance, cover crops, diversity in plants and soil organisms, improved root and soil structure leading to increased soil depth, high grazing residuals and true recovery times.
They warned against monocultures, over-worked and exposed soils, compaction and reliance on chemical fertilisers, fungicides and pesticides.
Barrett establishes up to 1000ha of cover crops annually with a cross-slot drill and a small amount of aerial application on the 9300ha Linnburn, which has some of the lowest rain in the country.
He uses seeds of 20 to 30 pasture varieties, mostly annuals and bi-annuals, including tap-rooted, tall species, legumes, cereals and vetches.
The crops establish even in dry summer months, provide short-term rotational grazing for sheep and cattle and right conditions to establish underground biota.
What limited rain falls is not wasted or evaporated but retained for root carbon feeding and plant breakdown building soil porosity.
After rolling and crimping the residual cover Barrett sows perennials like lucerne, clovers and grasses.
“We use a lot of different varieties because we are not after perfection or domination by one or two species.
“Diversity of plants equals less dependency on other inputs,” he said.
“We also encourage diversity because we don’t know all the answers.”
Some low-rate glyphosate use clears the weeds before cover cropping but weeds are important indicators of soil and plant populations.
Livestock numbers have recovered to between 20,000 and 25,000 units and the sheep genetics has moved from Merinos to Halfbreds plus an Angus cow herd.
Frew, a former farmer and agricultural chemical applicator, has a farming consultancy called Natural Performance.
“We are moving from complicated simplicity to simple complexity.
“We are constantly refining, changing, making mistakes, celebrating successes and recording our results.
“We want to share our experiences and results with all those prepared to listen.”
MORE:
linnburnstation.co.nz, jono@naturalperformance.co.nz
