Winnipeggers might be wondering where one of the autumn’s most familiar, although often unpopular, smells has gone.
A sharp drop in stubble burning fires in the Red River Valley has made the smell of smoke in the fall air all but non-existent this year.
As of Oct. 1, Manitoba Agriculture, Food and Rural Initiatives (MAFRI) had issued 131 burning permits to farmers in rural municipalities bordering Manitoba’s capital city. Last year a total of 321 permits were issued. In 2009, which saw a wet fall delay harvesting, 950 burning permits were issued.
Farmers in other areas are allowed to burn crop residue only when weather conditions allow the smoke to disperse and never at night.
Observers credit this year’s drop in fires to a combination of factors, including an increase in cereal straw baling, a decrease in cereal plantings and an increase in soybeans and corn, improved combine straw choppers and spreaders and even some changes in tillage practices.
But good fall weather gets most of the credit.
“It starts with the straw chopper and then the weather,” said Fannystelle farmer and seed grower Brian Nadeau.
It has been a dry fall, although with enough soil moisture to aid tillage. And it has been dry enough to bale and quickly remove straw from the field without causing ruts or compaction, Nadeau said.
“Around here there is a lot more baling than there used to be,” said Ingrid Kristjanson, MAFRI’s farm production adviser at Morris.
It has been a growing trend, accelerated last year by demand in the United States following a drought. There are also less cereal acres in the U.S.
Some farmers in the Red River Valley are also changing their approach to residue management and trying to work straw in rather than burn or bale it. Improved combine straw choppers are helping and some farmers are switching to vertical and high-impact tillage.
“But it’s the weather that’s going to make that final determination,” said Marla Riekman, MAFRI’s landscape stewardship specialist.
Nadeau agrees. He hasn’t burned stubble for two years. And he doesn’t bale his straw either, preferring to keep it and the nutrients it contains.
“But don’t ever take away our option of burning,” Nadeau stressed. “We try hard not to burn, but if we have a super-wet fall and we are fighting with mud I think you’d see more smoke.”
Straw burning in the 1980s flooded Winnipeg with acrid smoke, some years making breathing difficult, especially for asthmatics and the elderly. It also reduced visibility on some highways promoting a deluge of complaints, which resulted in the regulations in place now.
According to MAFRI, there’s 24 pounds an acre of nitrogen in the straw from a one-tonne-an-acre wheat crop. Ninety-eight per cent of it disappears when the straw is torched.
In addition there are three pounds of phosphorus and 32 pounds of potassium.
There’s even more nitrogen in flax straw — 31 pounds from a field yielding a half-tonne of flaxseed an acre.
(See straw nutrient table at: http://www.gov.mb.ca/agriculture/environment/soil-management/soil-management-guide/tillage-organic-matter-and-crop-residue-management.html).
“I feel strongly we have to change the way we work our land,” Nadeau said. And he has put his money where is mouth is, having purchased an expensive high-impact disc from Europe.
These implements cost $170,000 to $180,000, or almost double the price of a conventional discer. But they do a great job cutting and mixing the straw in the top couple of inches of soil, filling ruts and making a good seedbed, he said.
Cutting straw and then mixing it with the soil exposes it to soil microbes, which help break it down, Riekman said. Retaining straw also increases organic matter in the soil, improving its tilth.
“Soil structure is a hard one to sell,” she said. “It’s really important but we don’t put enough dollar value to it. Building up organic matter is really important.”
It also means adding more nitrogen because crop residue breaking down in the soil also ties up the nutrients, but only in the short term.
Nadeau said his high-impact disc exposes enough soil to help it warm up in the spring, while providing protection from wind erosion.
Nadeau is also applying liquid carbon to his straw, which he says assists in breaking it down. That, and high-impact tillage, are used in Europe.
“They’ve been farming for 1,000 years there and we’ve been farming for 100 here,” he said. “If we want to farm another 900 years here and feed the world we better take care of our soil. We’ve had it easy with new breaking. It takes time to ruin soil but we’re going there.”
Nadeau is so convinced the high-impact disc is the way to go so he sold his cultivator. But he jokes he’s going to build a concrete pad to display a cultivator just as some farms display antique plows.
“I want to show the grandkids what Grandpa used to farm with,” he said.