5.4.1. Stubble retention and no-till cropping

Stubble retention and no-till cropping are considered to have beneficial effects on soil moisture, soil conservation, biodiversity and (by avoiding stubble-burning) carbon sequestration.

A 2009 survey by CSIRO and GRDC reported that 92% of respondents in the region dubbed NSW Southern (covering Coolamon, Junee, Lockhart, Narrandera, Temora, Urana and Wagga Wagga) and 45% of respondents in the NSW Mallee (including Balranald) had used no-till cropping methods at least one, and 89% used it in 2008. It must be noted that these results are drawn from a very small number of respondents.

A survey of 700 landholders in the Murrumbidgee region (Davis, n.d.) reported that the most common form of stubble treatment was a combination of grazing, spraying and burning, followed by grazing only. Together with a combination of grazing and burning, and a regime involving grazing, cultivating, spraying and burning, these methods accounted for more than half of all stubble treatments. In total, almost 70% of respondents grazed stubbles, almost 50% burned stubbles, and almost 40% sprayed stubbles. (It is not clear to what extent each method was used by each respondent).

The survey also reported that 63% of respondents had sown crops into retained stubbles. Reasons cited for retaining stubbles in this way include conserving soil moisture (roughly 75%), to increase the organic matter component of the soil (almost 70%), to improve soil structure (slightly more than 60%) and to maintain groundcover and prevent erosion (roughly 55%). Slightly fewer than 20% of those who had sown into retained stubbles did so to reduce pollution, nutrient loss and/or erosion from burning.

References and Resources
• Australian Government – Grains Development and Research Corporation and CSIRO. 2009. Adoption of no-till cropping practices in Australian grain growing regions.

• Davis, V (Murrumbidgee CMA). Undated. Dryland Farming Systems Survey: Final Report.