Controlled traffic, together with Australian developments in precision guidance, look like best bets for farmers seeking another avenue to secure the economics and sustainability of their operations in a climate of shrinking margins and environmental constraints to production.
Speaking at the Australian Agronomy Conference in Hobart, JeffTuliberg of the University of Queensland said the area of crops now sown under controlled-traffic conditions in Australia, including raised-bed farming, exceeded 0.5 million hectares.
Dr Tullberg said that about half the power output of a tractor could be used in 'undoing' the traffic effects of its own wheels on the soil. Soil compaction resulted from pressure produced by tractor wheels and those of other implements. This led to reduced water infiltration, reduced soil water storage, less earthworm activity and greater potential for erosion.
"In plain language, half the total power output of a tractor is dissipated in soil degradation," he said. "When traffic is controlled, tractor size and fuel requirements are typically reduced by 50 per cent, regardless of other changes, and this has been achieved in practice by some farmers.
"Farmers adopting controlled traffic often report reductions in the time and material inputs to operations of 10 to 30 per cent. Controlled-traffic farmers are using much less tillage than they used to and some would claim that controlled traffic is a, prerequisite ofzero tillage."
At the conference, which was supported by growers and the Federal Government through the GRDC, Dr Tullberg said that, given the economic and environmental advantages of controlled-traffic farming, the question arose as to why it had been "unnoticed for so long".
He suggested that:
- visible evidence of plough pans was "hidden" by the tillage over them
- farmers were concerned that they would have to change all their machinery
- some agricultural scientists saw controlled traffic as a competitive idea to zero tillage
- unlike zero tillage and deep tillage, no major group of multinational agricultural suppliers with large advertiSing budgets would profit from controlled traffic
- established agricultural systems worked with compacted soils, but there was much to learn about the agronomy and practical management of non-compacted soil.
Dr Tullberg said farmers could start to control traffic using very simple machinery systems. However, there were benefits from greater precision in operations - examples being more targeted and efficient chemical and fertiliser applications. He said Australian companies currently lead the world in the development of high-precision guidance.
"It would be even better to see this commercial initiative enhanced by a major interdisciplinary project to develop the full potential of high-precision agriculture and further improve the economics and sustainability of farming."
Program 4.1.4 Contact: Dr Jeff Tullberg 07 6470 1354 email email@example.com