Despite widespread interest in and experience with retaining crop stubbles on their paddocks as part of crop rotations, a Charles Sturt University (CSU) study shows that many grain growers still prefer to burn stubble.

Study author Associate Professor Vaughan Higgins, senior social researcher with the Graham Centre for Agricultural Innovation in Wagga Wagga, said, "Personal values, cost, and the biophysical impacts of burning were important for grain growers rather than any outside pressures in deciding whether retain crop stubble from the previous season."

Professor Higgins found growers were well aware of the economic and environmental benefits associated with stubble retention, such as reduced costs and labour intensity as well improved soil structure and better water retention in the soil.

"However, our interviewees reported a number of technical, biophysical and biological challenges as well as higher workloads when they retained crop stubble as part of their management," he said.

"When they burnt crop residues, they observed higher crop yields, had fewer problems with disease, weeds, pests and machinery, and used less chemicals and pesticides. They also felt there was little social pressure to change and they wanted to remain flexible in their management decisions.

"Consequently, many growers have partially adopted stubble retention techniques in recent years but continue to burn stubble selectively, and some reluctantly, as part of their management 'toolkit'."

In recent years, the Federal Government has promoted stubble retention to sequester carbon in farm soils.

"However, interviewees saw few benefits in taking part in 'soil carbon' initiatives. They saw few economic benefits for the farm business, believed other existing environmental practices might suffer, saw problems with accurately measuring soil carbon, and acknowledged inconclusive scientific evidence for soil carbon," Professor Higgins said.

"It was not a priority for growers and they were sceptical of the concept."

The study reports on interviews with grower groups as well as individual growers during 2013 from grain growing regions as far as Geelong in Victoria and Condoblin, NSW. These growers were involved with the 'Enabling landholders to adopt profitable and sustainable carbon cropping practices' project run by the Graham Centre.