Constraints to stubble retention and finding answers to issues blocking its wholesale adoption are the focus of researchers at the EH Graham Centre at Wagga Wagga.

Southern NSW farmers quickly adopted strategies to minimise cultivations since the early 1980s, when knockdown herbicides and reduced tillage replaced multiple cultivations.

Whilst conservation farming has progressed in leaps and bounds however, the move away from stubble burning to full retention has faltered.

A 2006 Murrumbidgee Catchment Management Authority survey by Vivian Davis backs up 2001 Australian Bureau of Statistics data that indicates approximately 50 per cent of southern NSW stubbles are likely to be burnt following "average" seasons (which are increasingly hard to define).

Many of these are classed as strategic burns, delayed until just prior to sowing in a bid to maximise moisture retention and erosion control over summer and early autumn.

Reasons for burning include machinery constraints, weed and disease management, while the common reasons for retaining stubble include erosion management, moisture retention, improved soil condition and labour saving.

Now the Conservation Farming and Stubble Management Initiative of the EH Graham Centre (an alliance between NSW DPI and Charles Sturt University), lead by Professor Len Wade, will target research to provide clear guidelines for stubble retention in the southern cropping zone, including the impact on human health and water and air quality.

The extension component will identify management strategies which farmers from varied locations are using to retain stubbles and provide comparisons of the economic and environmental costs and benefits of the stubble management practices currently used.

Contact Professor Len Wade, Wagga Wagga, (02) 6933 2523, lwade@csu.edu.au