Eliminating stubble burning from their residue management practices has significantly reduced management stress and resulted in a multitude of benefits for the Heggaton family, 20 kilometres south of Kojonup.
“We found stubble burning a hazardous process and environmentally unfriendly,” says James Heggaton, who works with his parents on their mixed-farming enterprise.
On average, the property receives 500 millimetres of rain a year, of which about 375mm is growing-season rainfall. This can generate significant stubble loads of up to five tonnes per hectare from cereal crops.
“Previously we would burn stubble in cereal paddocks and rake and burn canola stubble. It was a lot of work and the stress of a potential escaped fire was taking its toll on managing our cropping system,” James says.
“An additional driver for the practice change was the fact that we have been experiencing reduced total rainfall and increased summer rainfall.”
James started making changes to residue management practices in 2014.
“It was a three-year transition to put the new stubble management practice into place, beginning with altering practices slowly, piecing together information from attending field days and discussing with trusted advisers,” James says.
“We now chop and spread all stubble over a 12-metre width behind the header, ensuring we have a good, even spread and retain standing stubble to a height of 200 to 250 millimetres, which fits into the controlled-traffic system.”
This covers any bare earth, improving water retention and capturing summer rains, preventing wind and rain erosion and smothering any summer weeds. The remaining standing stubble acts as a wick for moisture into the soil.
The Heggatons are now sowing at 300mm row spacing and near furrow sowing, sowing close to the standing stubble to access retained moisture and enabling crop establishment on much less moisture.
“Implement guidance has been a game-changer for this as we can get our sowing bars within two centimetres of the stubble and we use optical spraying to control any summer fallow weeds. Chaff decks and tramlining are another important part of our residue management,” James says.
Crop diversity, using a rotation of faba beans, wheat, canola and barley, also assists in managing stubble loads as the break crops – canola and faba beans – produce less stubble.
James says they are beginning to see clear improvements in their soils with increased carbon and nitrogen cycling and increased microbial activity. “Our soils are becoming more spongy and friable, and we are harvesting more grain from less water.”