Persistent pasture pays in the long term

But the high cost of establishing improved pastures is of concern to landholders if that pasture is not long lived, and Phil Graham, consultant with Graham Advisory, Yass, noted persistence of pasture species is already a problem.

"Climate pressures will only increase this problem to an extent that sowing new pastures could become a questionable investment decision," Mr Graham said.

"And species selection and the mix used is critical."

Mr Graham made reference to survey work carried out in the early 2000's by research agronomists Jim Virgona and Shane Hildebrand which showed at that time the persistence of many sown species was already an issue in the high rainfall zone of southern NSW.

"That work agreed with similar pasture research carried out in the US which indicated as the number of species in the mix sown increases persistence of the species decreases," he said.

"And with the cost of establishing a new pasture at around $500/ha if lime is applied pre-sowing and the cost of seed at around $15kg/ha there needs to be a substantial increase in stocking rate and longevity of the pasture to substantiate the cost."

Mr Graham used a basis of cost comparison, current sheep gross margins of $40 to $50/DSE and extrapolated an increase of stocking rate by six DSE/ha, and if the pasture is maintained for at least ten years, then that new pasture is capable of providing a reasonable return on the investment.

But, Mr Graham noted, results of the Virgona/Hildebrand survey and recent experience shows that it is unlikely that the increased stocking rate will be maintained for ten years.

"There might be a short-term increase in stocking rate, say to 12 DSE for five years, but if after that time it drops back to nine DSE/ha, then the returns are looking questionable at $50/DSE and a disaster at $41/DSE."

It is axiomatic that the short-term (three to five years) life of a pasture is costly to a grazing business based on permanent pastures, and Mr Graham pointed to problems caused by the relative lack of availability of pasture seed.

"In the last few years there has been a shortage of pasture seed and pastures were sown with the seed available rather than the species that suited the paddocks," he said.

"The impacts of this market situation will be seen over the next three years as inappropriate species disappear."

Mr Graham further acknowledged that changes in the local climate have and will continue to place pressure on perennial pastures.

"If stocking rates are not adjusted to reflect the changes in pasture production, then this will add to the persistence problem we already have but this impact will vary depending on location and soil type," he said.

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