U.S. Department of Agriculture researchers looked at the long-term effects of three cropping rotations in Montana — summer fallow-wheat, no-till continuous wheat and no-till wheat-pea.

After crunching the data, they concluded that the wheat-pea rotation is the most sustainable.

“No-till continuous spring wheat and no-till spring wheat-pea reduced greenhouse gas emissions per unit area, as well as per unit crop yield compared to continuous till spring wheat-fallow, due to increased carbon sequestration,” says the study, published late September in the Journal of Environmental Quality.

The researchers also found that continuous wheat causes disease issues and cuts into yields over time.

“For sustaining long-term crop yields and reducing GHG emissions, NTWP (no-till wheat pea) may be recommended as an ideal dryland cropping system in the semiarid condition of the U.S. northern Great Plains.”

The finding isn’t a shock, considering field peas require less fertilizer, and zero tillage has a proven track record of reducing soil erosion and enhancing the health of the soil.

However, the USDA scientists also quantified the environmental benefits of reduced tillage and the environmental consequences of summer fallow.

The researchers studied the three dryland cropping systems at the USDA centre in Sidney, Montana, looking at data that stretches back 34 years.

They collected nitrous oxide and methane emissions from the cropland throughout the year, from 2012-19. They also estimated the carbon sequestration rates of the three rotations.

Using the emissions data and sequestration rates, the scientists calculated the net greenhouse gas emissions from the cropland.

“Overall, the no-till continuous cropping systems reduced net GHG balance by 66 to 149 percent compared to the conventional till crop-fallow system,” they said.

Of note, the no-till continuous wheat (NTCW) had a higher amount of carbon sequestration when compared to the no-till wheat pea rotation.

“(The) slower decomposition of crop residue due to higher C/N (carbon/nitrogen) ratio of spring wheat residue compared to pea residue probably increased soil organic carbon for NTCW compared to NTWP (no till wheat-pea).”

The scientists learned that continuous wheat increased pest pressure and soil acidity from the annual applications of fertilizer compared to the wheat-pea rotation.

Those agronomic issues reduced wheat yields and the return on investment for growers.

The USDA study on the sustainability benefits of no till and having a legume in the rotation is similar to the findings of a report from the University of Saskatchewan.

In January, the Global Institute for Food Security at the U of S concluded that Saskatchewan farmers are producing crops with relatively low emissions when compared to growers in Australia, Europe and the United States.

“The results are driven by the widespread adoption in Saskatchewan of agricultural innovations and sustainable farming practices that have significantly reduced the amount of inputs and emissions needed to farm each acre of land,” said Steve Webb, chief executive officer of the Global Institute for Food Security.

“The sustainable practices include reduced tillage, the adoption of herbicide-tolerant canola, the variable-rate application of fertilizer, a robust crop rotation system and the production of nitrogen-fixing pulse crops.”

The report, “Critical Ground: Why Soil is Essential to Canada’s Economic, Environmental, Human and Social Health” was released by the Senate’s agriculture and forestry committee in June.

The document argued for a federal long-term soil conservation and protection strategy. Changes including widespread no-till adoption have helped improve soil moisture management and crop yields, the report said, but soil degradation and loss of agricultural land have continued nationwide.

Climate change, extreme weather events, urbanization and misread outcomes of soil management practices are also part of the problem, the report said, as is the lack of a central database and consensus on how soil health should be measured, reported and verified.

The committee suggested that the federal government appoint a national soils advocate and designate soil as a strategic national asset.

A significant focus would land on the Prairies, home to most of Canada’s agricultural soil, should report recommendations be accepted.

KAP member Mike Duguid proposed the roundtable at the group’s July advisory council meeting. His motion would see KAP collaborate, organize and facilitate stakeholder groups in its network to form the group. The resulting roundtable would discuss all aspects of soil health and ensure that provincial and federal efforts remain focused on farmer-led practices and initiatives.

“KAP is taking a leadership role on this,” president Jill Verwey said, adding that KAP is in talks with Senator Rob Black, who chaired the Senate committee, regarding the report.

“In our correspondence, hopefully we’ll be able to engage with producers and have some real, wholesome discussions as to how we accomplish those outcomes.”

Duncan Morrison, KAP member and executive director of the Manitoba Forage and Grassland Association, seconded the motion. The proposal was carried with 78 per cent of delegates voting in favour.

It’s important for KAP to work with groups like the forage and grassland association to ensure the safety of Canadian soil, said Duguid, who is also chair of the MFGA.

“We feel that the more organizations that support soil health, the better. When you look at the state of some of the soils, it’s very important to watch out for … desertification in the big picture.”

The impact that soil has on grasslands, biodiversity, clean water and more cannot be understated, Duguid added. KAP will specifically look at how soil bases can be improved to prevent erosion and topsoil loss into water systems.

“That’s where we feel that the more organizations that speak about it, the better it is,” he said.

Morrison added that his organization would benefit from collaboration and leadership provided by KAP. The MFGA regularly consults with different commodity groups from the beef, dairy, sheep and bison sectors, and has heard calls for a soil-oriented organization.

“We’re involved in a lot of discussions at our board and at our farm level and we think that this will help string together some of the main players in a soil health discussion,” Morrison said.

He also noted the increased profile that soil health has been enjoying among industry and other individuals.

“It’s clearly evident that soil is important to all of us, and I see KAP as (taking) a leadership role,” he said.

Tim Poole, species at risk biologist with the provincial government, and Marissa Bedard and Meredith Stoesz from Important Bird Areas, recently wrapped up field visits to nine regenerative agriculture farms operated by members of the MFGA.

On these farms, producers focus on healthy soil practices including no-till/minimum tillage techniques, cover crops, crop rotation, using compost and manure, and managed grazing.

Last year, the first bird survey provided information on how these practices affect different bird species. Bird populations across four farms in western Manitoba were counted.

With nine farms involved this year, the next steps for the survey will see researchers collate information into a report on species and specific on-farm practices – particularly those involving soil health – and landscape scope, including grasslands and wetlands.

“There’s a real distinct reason we’re doing this … and a real particular interest in getting those benchmarks via biodiversity of the bird populations and abundance, and then collating that to how our people are farming when it comes to soil health,” said MFGA executive director Duncan Morrison. “It’s getting that information that doesn’t exist on a wide number of regen-ag practising farms.”

MFGA uses the survey to understand and highlight the link between soil-focused agriculture practices and intact natural habitats for birds, with a special emphasis on species at risk such as bobolink and Sprague’s pipit.

The federal government has emphasized the importance of biodiversity in its 2030 National Biodiversity Strategy, created through Environment and Climate Change Canada in 2023.

“The federal government has told us that biodiversity is important to our nation, and we’re responding to the signals we receive from Environment Canada, who say biodiversity may be a climate change mitigation tool,” Morrison said.

“It seems likely they’re pursuing that in their approach, and we’re listening. We’re trying to make sure that our farmers are properly represented in the provision of biodiversity.”

Though no official report has been released, experts said this year’s survey results show positive numbers. Jacques Saquet, an MFGA board member and bison farmer, had a positive experience taking part in the survey.

“What a tremendous morning to carry out a bird survey,” he said in a July 19 bulletin sent by MFGA. “We had lots of mosquitoes, no wood ticks because of heavy dew on the tall grasses, and the best bonus of the outing — five adult female wapiti with three young.”

A variety of birds were found on each farm that has taken part in the survey, Morrison said, including species at risk. More information on the results will be announced soon.

Kevin Elmy, cover crop consultant with Imperial Seed, urged producers to design systems that will increase species diversity. A truly diverse system, he said, should include a legume, grass and a forb to support a field’s microbiology and fight weeds.

“When we don’t have representation of a functional plant family, Mother Nature gives it to us,” Elmy said.

That plant mix trifecta is especially important for those trying to tackle organic production without tillage, he said. He urged attendees to change how they think about weeds. Instead of seeing them as pests, think of them as soil indicators.

He used the example of quack grass taking over a field. The weed is known to thrive in low-calcium soils and might therefore indicate a nutrition problem.

If the producer addressed that deficiency with a cover crop, Elmy suggested including something in the mix that would accumulate calcium.

“Grow something with lots of cell walls, especially in the soil,” he said. “So, either a high root mass or turnips, radishes, beets; they have lots and lots of calcium.”

The best control is less about destroying weeds and more about replacing them with a similar, intentional plant, said Elmy. Getting rid of weeds helps the crop but also robs the field of organic matter and nutrients tied up in weed biomass.

“It’s ecological advantage,” he said. “Well, OK. We’ll take that away. We’re going to give (the system) what it’s searching for.”

No-till and organic production often dovetail in philosophies about sustainability, but the latter generally relies on mechanical weed control and tillage. That challenge was highlighted in the field day’s no-till trial. The plot, hosted by Living Skies Organics and its owner, Jade Leicht, was heavily weeded.

The trial was a side-by-side comparison of conventional and no-till organic production. Oats were broadcast with a cover crop of red clover. Leicht said they’re trying no-till as a long-term strategy and intend to mow the plot next year.

“They’re just trial periods right now,” he said. “And then it’s learning by doing, that’s the thing you do.”

He’s unsure what seed he will add next year, but intends to use some of Elmy’s strategies.

Despite the challenges of incorporating no-till in organic production, Elmy says he has clients who make it work.

He compared the bacteria, fungi and nutrient cycling of the soil. In the tilled crop, the balance of bacteria to fungi weighs in favour of bacteria, he said, while fungi populations rise under no-till conditions.

“Bacteria cycle nutrients fast,” Elmy said. “So over here (the no-till), our bacteria slow down … our nutrient cycles slow down, so we get more of these perennial weeds.

“This is where we have to look at microbial companies and the amino acid groups. We need to add and support more bacteria to get our nutrient cycles going and to get the nutrient balance.”

A company with roots in Australia, Canada and now the U.S. has a solution, a jet of high-pressure water to carve open the soil so that seed openers and placement technology have the best chance to put the seed exactly where it should be.

Opener discs can “hairpin that residue into the soil. And when they do that, they’re not going to get seed germination or yield,” says Michael Cully, CEO of Susterre, which is developing the water jet seed trench opening technology.

Susterre has licenced the technology from I-Cubed Industry Innovators, an Ontario company that specializes in industrial uses of high-pressure water and automated manufacturing solutions. I-Cubed remains an investor in the company and does the manufacturing of the system.

I-Cubed brought the idea to Ontario from Australia, but isn’t focused on agriculture, so was happy to have a startup company take on the final development and commercialization of the technology.

Michael Cully, CEO of the company, made a pitch for funding to a group of venture capitalists at the Agri Tech Venture Forum in Toronto recently.

Susterre is one of the first projects funded by Carrot Ventures, a venture studio administered by Verdex Capital, formerly known as the AVAC Group.

Carrot Ventures takes direct aim at the Canadian inability to commercialize enough of its research and technology compared to other countries. It looks for great technology or innovations, then forms a company to manage it, recruits a CEO and helps take the product to market.

Cully was recruited to manage Susterre after a career that involved work for AGCO, JCB and another agriculture technology startup.

The Susterre system attaches to a planter’s toolbar so that the water is sprayed in front of the disc openers and seed placement and closing system.

A ski presses down the residue and then water jets move water at 60,000 lbs per square inch to cut open the ground. A fine jet of water is all that’s needed to open the residue by one-seven thousandths of an inch before the disc openers make a wider slit for the seed.

The jets “cut metal, so they can cut through anything in the field,” says Cully.

The system needs about 10 gallons per acre and starter fertilizer can be used as the cutting liquid, so standard liquid fertilizer bins are good enough.

“It takes the planter and puts it on steroids because the delivery of the seed to depth is so much better with our system,” says Cully.

Another advantage, says Cully, is that there isn’t as much need to wait for the ground to dry with a water jet opener. If the tractor can get on the field without making ruts, then the planter can run.

The limitation is horsepower to power the pumps as they take about 12.5 horsepower per row so a 12-row planter needs about 150 horsepower just to run the pumps. On a planter with up to 18 rows, the intensifier pump can be run by hydraulic pumps powered by the power take off (PTO). Larger planters will need an external power source, at this point a generator on a cart between the tractor and the planter.

The system is aimed at crops with row spacing above 15 inches. Cully says they expect farmers who currently plant using no-till and farmers who have held back from using no-till because of the challenges of excess residue will be customers.

“We can be installed on any make or model of planter, so we could take a conventional farmer, add our system and they would be a no-till farmer.”

Cully says they believe that the system would pay for itself in two years with the reduction in costs around no-till, reductions in overseeding and a yield increase.

The good news is that canola-based SAF qualifies for the base blender’s credit of US$1.25 per gallon because it was previously approved by the U.S. Environmental Protection Agency as an eligible feedstock.

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“We’re pleased to see that,” said Chris Vervaet, executive director of the Canadian Oilseed Processors Association.

“At least we’ll qualify for that base amount.”

The bad news is that it does not qualify for the additional 50 cent per gallon blender’s credit that is up for grabs.

“Canola appears to be on the outside looking in,” he said.

The U.S. Department of Treasury and Internal Revenue Service used a modified version of the GREET life cycle analysis model to assess various SAF feedstocks.

The 40BSAF-GREET 2024 model determined that canola SAF reduces greenhouse gas emissions by 37 per cent, falling short of the 50 per cent threshold to qualify for the additional 50 cent credit.

Vervaet said the model contained flawed assumptions and outdated data that need to be addressed with government regulators.

The new guidance applies to the 40B SAF blender’s tax credit contained in the Inflation Reduction Act and will be applied retroactively for 2023 and 2024.

That blender’s tax credit will be eliminated in 2025 and is being replaced by 45Z, a producer’s tax credit that applies to SAF, biodiesel and renewable diesel.

It takes effect Jan. 1, 2025, and expires Dec. 31, 2027.

Vervaet said SAF holds incredible potential for the canola sector.

“We want to compete in that marketplace, there’s no doubt about it,” he said.

However, it is equally important for canola to maintain its foothold in the biodiesel and renewable diesel markets.

Vervaet said the 40B SAF rules are being closely scrutinized by commodity groups because they feel they will be a precursor for what’s to come with 45Z, which is the more all-encompassing tax credit.

One unique feature of the 40B rules is that commodity groups can improve their carbon intensity scores by using specific climate-smart agricultural practices.

However, that feature is only available for corn ethanol- and soybean-based SAF, much to the chagrin of the canola sector.

The soybean sector can increase the amount of its tax credit by cultivating the oilseed using both no-till and cover cropping practices.

The American Soybean Association is concerned that mandating only those two practices among various sustainability measures may limit soybean oil’s viability as a SAF feedstock.

“Moreover, the feasibility of implementing no-till and cover-cropping varies across different regions of the soy-growing belt, potentially leading to regional disparities,” the association said in a news release.

The National Corn Growers Association said it is troubled that the model requires corn farmers to bundle the use of no-till practices, enhanced efficiency fertilizers and cover crops to qualify for the credit.

“This requirement in GREET will significantly hinder the chances corn growers have in accessing the sustainable aviation fuel market,” NCGA president Harold Wolle said in a news release.

He noted that cover crops are difficult, if not impossible, to grow in drier climates.

Vervaet said the good news is that the U.S. government has made it clear there is room to update and change the GREET model prior to implementation of the 45Z credit.

Canada’s canola sector will be working with its U.S. counterpart to lobby for changes in how the model treats canola-based biofuel.

“We’re going to be putting our shoulder behind the wheel to get a better carbon intensity score for canola,” he said.

Contact sean.pratt@producer.com

Planting cover crops and reducing tillage are key to the USDA’s plan to slash agriculture’s 10 per cent contribution to U.S. greenhouse gas emissions as the U.S. pursues net-zero by 2050. Ethanol producers also hope those practices will help them secure lucrative tax credits for sustainable aviation fuel (SAF) passed in the Inflation Reduction Act.

But the farming techniques, which will receive an extra funding boost from Biden’s signature climate law, may not permanently sequester much atmospheric carbon in the soil, according to five soil scientists and researchers who spoke about the science.

Four other soil scientists, and the USDA, said the practices can store various amounts of soil carbon, but circumstances will dictate how much and for how long.

“The adoption and persistent use of no-till and cover crops are key for the sequestration of carbon on working croplands,” said a USDA spokesperson.

All experts interviewed by Reuters agreed that no-till and cover crops can have significant environmental benefits, such as preventing soil erosion and increasing biodiversity. Yet five of them expressed skepticism about tying climate policy and public money to the practices.

“Will it help with climate adaptation? Absolutely. Should it serve as an offset for more permanent and long-lived pollutants? Absolutely not,” said Daniel Rath, an agricultural soil carbon scientist at the Natural Resources Defense Council.

The USDA has spent $1.3 billion in financial assistance to farmers for planting and managing cover crops and $224 million for implementing no- or reduced-till since 2014, according to agency data. That figure is minuscule compared to total USDA spending, but does amount to about eight per cent of its farm conservation spending in that period.

“If we really want to offset or mitigate climate change, we need to think about different systems,” said Humberto Blanco, an agronomy professor at the University of Nebraska-Lincoln. “We need to think about more aggressive strategies.”

Adoption of cover crops and no-till has risen in the past decade; now, 11 per cent of farms plant cover crops and about 40 per cent use minimal or no tilling, according to the most recent USDA agricultural census.

Under the right conditions, both practices can be positive for the climate, said scientists.

“If a farmer is using cover crops and getting good growth in the fall and spring, and they’re doing minimal tillage, on most soils, they’re going to add soil carbon over time,” said Robert Myers, a professor at the University of Missouri and regional director of extension programs at a USDA research site.

Five other experts said no-till farming commonly results in a higher concentration of carbon in the soil surface but a decrease deeper in the profile, resulting in a net zero gain.

Seven experts said the climate benefits of no-till and cover crop techniques can be lessened or reversed if farmers plow their fields again.

“Even if you do build up some extra carbon under reduced tillage, if you then do a traditional plowing, the evidence seems to be that you quite quickly lose the carbon that you’ve been building up,” said David Powlson, senior fellow at Rothamsted Research, an agricultural research institution.

Only 21 per cent of farmers report using no-till continuously, according to the 2022 farm census, and about a third alternate reduced tilling with conventional tilling, a 2018 USDA report showed.

A USDA standards document for no-till says loss of carbon in the soil is directly tied to the amount and intensity of tillage, and other factors like soil moisture and temperature.

As for the SAF tax credit, the Treasury Department is expected to finalize details in coming weeks. The $1.25 per gallon credit is aimed at producers who prove their fuel can cut emissions 50 per cent from those of straight jet fuel.

The program will likely require ethanol producers to source corn from farmers using cover crops, reduced tilling or efficient fertilizer application. The USDA declined to comment on what the fertilizer application would entail.