Livestock

No more ‘normal’

By Country News

Having the confidence and impetus to make decisions on grazing management in tough seasons is a powerful mental step forward, according to grazing consultant Bart Davidson.

Mr Davidson, of MaiaGrazing, believes farmers tend to be trapped in a ‘‘mental model of how their farm works in normal years’’.

‘‘Seasonality is most variable and changing — so-called normal years just don’t statistically happen very often,’’ he said.

‘‘Drought is not the problem; we have to get used to the fact drought is inevitable — blaming the weather is just us kicking the cat.

‘‘This is all about me as a manager deciding what information I need to make better decisions at a time when it is going to benefit me, the family and the farm, and not make those decisions when it’s too late.’’

Mr Davidson will be a guest speaker at the MerinoLink and Merino Lifetime Productivity Project field day at the CSIRO in Armidale on June 20.

He considers himself a mathematical agronomist and, along with a broad team, has developed an online grazing management tool to maximise pasture and profit in good and poor seasons.

The tool gives producers the ability to unlock strategies for optimising grazing pressure and stocking rate in a timely manner.

To illustrate the power of information in dry times, Mr Davidson monitored a 150ha paddock over four years to assess the impact of overgrazing on its productive capacity.

‘‘If productive capacity changes, the ability of the paddock to convert moisture into grass has either improved or degraded,’’ he said.

‘‘Depending on the resilience or fragility of the soil and pasture, it will be damaged (by overgrazing).’’

Mr Davidson said more than 25 per cent of pasture productivity could be lost by not matching stocking rate to carrying capacity during dry times.

He followed every grazing over a four-year period of the monitored 150ha paddock, and found an opportunity cost of 1.27tonnes of dry matter per hectare — grass it would have grown if grazing pressure was reduced at key times, and increased when seasons allowed.

‘‘The paddock lost $127/ha worth of production at replacement cost on the dry matter,’’ he said.

‘‘Over 150ha, the cost is above $24000 and we found as long as 33 months after being overgrazed, production was still down 30 per cent compared to the paddock’s long-term capacity to convert actual rainfall into consumable grass.’’