The value of keeping accurate data has been underlined in a major rotation-grazing subdivision on Rupert Murdoch's Cavan Station near Yass which covers about one third of the historic 10,000-hectare property.
The aim of slicing 58 paddocks into 118 on a 3000ha portion of Cavan was to more closely align stocking rate with rainfall and available pasture to achieve the best production and environmental outcomes.
Bart Davidson, a senior consultant with Maia Grazing, explained the results to a webinar audience organised by MerinoLink.
Apart from soil fertility, the key grazing variables were stocking rate, rain, stock density and pasture recovery time, Mr Davidson said.
He said Cavan had one of the best data sets in rural Australia which significantly improved decision making by closing the "feedback loop".
"It's about making the best decisions," Mr Davidson said.
The average paddock size was cut from 87ha to 26ha while grazing density per graze was increased by 250 per cent and the duration of grazing days reduced by 58pc from 40 days to 17 days.
Average grass yield increased 68pc from 220 kilogram per ha per 100mm of rain to 369kg.
Cavan's long-term rainfall average is 730mm but the average for the past five years has been 620mm.
Rainfall in 2018-19 was only 465mm but wool production per ha for each 100mm of rain was 4.62kg which was higher than the previous five years when annual rainfall ranged from 852mm to 567mm.
Over the five years wool output per ha per 100mm of rain had risen from 3.62kg tro 4.62kg (with a downward blip in 2016-17 to 2.58kg despite 852mm of rain).
Positive changes had been achieved in seriously challenging seasons, Mr Davidson said.
Rolling annual rainfall at Cavan had only been above average for 11 of the past 83 months.
Since about the end of 2017 actual stocking rates (DSEs per ha) had closely aligned with suggested stocking rates.
Mr Davidson said the results from Cavan showed subdivision fencing, water and data-driven management could add an extra DSE for $90 compared with buying land in the area for $1000 a DSE.
The fencing and extra water points could be paid for in a year, he said. He also said any subdivision shouldn't be about building great fences. The fences just needed to "work" he told the webinar audience.
Two Cavan employees, Will Wragg and Tom Deery, participated in the webinar.
Mr Wragg said data was collected "on the go" using a phone app.
The data allowed better forecasting of feed availability and early decision-making, he said.