Smoke has drifted into town as crop stubble burnoffs on the outskirts of Ashburton have been under way in recent weeks.
The smoke has sparked complaints to Environment Canterbury (ECan).
Late summer and early autumn is when farmers in the district burn off paddocks of crop stubble left after harvest.
The fires cause spectacular smoke clouds, which quickly dissipate and sometimes drift over urban areas.
Last Friday about 5pm smoke was particularly noticeable, causing a haze across central Ashburton.
ECan acting southern compliance team leader Steve Firth said the regional council had received seven smoke complaints relating to crop stubble burning since February 1.
Air monitoring equipment had recorded no high-pollution events, but there had been some hourly spikes in particulate matter readings, the highest being on Friday evening.
Crop burnoffs have also resulted in several false alarm callouts for the Ashburton Volunteer Fire Brigade over the last week.
About 4.45pm on Friday, the brigade was called to smoke on the eastern outskirts of Ashburton.
Chief Jeff Marshall said the brigade headed off in that direction, but by the time they got there the smoke had dissipated and was over the west side of Ashburton.
Smoke from crop stubble burnoffs they responded to generally exhibited the same pattern.
‘‘It (smoke) only lasts for a short time, and it bypasses. By the time we get there, we often can’t pinpoint the exact area,’’ Marshall said.
Meanwhile, residents have been commenting on The Ashburton Courier Facebook page about smoke in the town, including on Friday evening.
Some residents like the smell of crop stubble smoke, some complain about it filling their homes, causing coughing and preventing them from hanging out washing.
RULES DICTATE BURNOFFS FOR FARMERS
Farmers follow strict rules to try and prevent smoke spreading from crop stubble burnoffs, says Foundation for Arable Research’s chief executive.
Dr Alison Stewart was commenting following burnoff smoke drifting across Ashburton in recent weeks.
‘‘But the reality is that a sudden unexpected wind change can create an unintentional smoke hazard,’’ Stewart said.
‘‘The grower could have put in place all of the required management practices and unfortunately still get caught out.’’
Any grower burning crop residue within 5km of Ashburton or Timaru has to get a Consent to Burn from ECan.
This is in addition to a permit from Fire and Emergency NZ, and entails agreement to follow a detailed set of rules around where, when and how the burnoff is conducted.
‘‘If a grower has not followed the rules then the council has the ability to cancel the Consent to Burn,’’ Stewart said.
‘‘So there are very strict rules in place to try and prevent smoke spreading, particularly towards any residential areas.’’
Federated Farmers arable chair David Birkett said this season may be worse than normal due to summer conditions having led to damp crop stubble, which could create more smoke.
Meanwhile, burnoffs are recognised by farmers as an effective way to manage crop residue.
Their advantages include minimising cultivation intensity and fuel use, supporting sustainable weed management, maximising soil and seedbed quality, enhancing farm system productivity, and reducing pest and disease problems.
