South Canterbury cropping farmers have been asked to take extra care when burning off this season, as many parts of the region dry out.
Burnoffs were done strategically by farmers after harvesting to prepare the paddock for the next crop rotation, Federated Farmers South Canterbury grain and seed chairman Colin Hurst said.
"There's no question about it. We always need to be extra careful."
He was aware burnoffs could be a nuisance, but they were done only for a short period of the year and not on all crops every year.
"It's strategic burning, it's within a rotation and it's not every paddock every year and it's a very good management tool to deal with slugs and weeds."
Farmers were also still able to carry out burnoffs during a fire ban if they had a permit.
The alternative was to plough the straw under the soil or bale it up. There was not always a market for the straw and making it often meant more costs to the farmer, he said.
If left on the paddock, the stubble created a buildup of trash and it attracted insects and slugs. As the next crop was emerging, the slugs would eat all the plants. Pesticides could be used, but they were not that good for the environment, Mr Hurst said.
Science had shown that burnoffs were more environmentally friendly than the alternative, which was intense cultivation, he said.
Mr Hurst said he was "fanatical" about making sure smoke did not travel across the road and create a hazard when he did burnoffs on his farm, next to the main highway near Makikihi.
"We've waited up to three weeks sometimes to make sure we get the right conditions."
Farmers had a code of practice developed by the Mid Canterbury branch of Federated Farmers that was followed when they wanted to do a burnoff.
One of the major risks was if the wind changed. That had happened, but it was rare. If the public had concerns, they should contact him, he said.
- The Timaru Herald