Science

These techniques are helping Prairie farmers grow crops despite drought

More irrigation, drought-tolerant crop species and new management practices are all being considered as Prairie farmers continue to grapple with the devastating impacts of this year’s drought.

'It's these type of years that you can see the drastic difference,' says Saskatchewan dairy farmer

Paul Kernaleguen's dairy farm is located just outside Birch Hills, Sask. He says he has fared this year's drought better than most farmers because he practises an agricultural technique called cover cropping. (Submitted by Paul Kernaleguen)

Paul Kernaleguen puts his keys in the ignition and drives his truck through his green, swaying fields just outside Birch Hills, Sask.

At first glance, you can't tell Kernaleguen is at the epicentre of one of the worst droughts to hit the Prairies in over 50 years.

The dairy farmer's lush, green crops stand waist-high — in stark contrast to his neighbours' dry, yellowing fields.

Although drought is a natural part of the climate cycle in the Prairies, climate researchers are warning that droughts will become more common and more intense.

Jame Famiglietti is the executive director of the University of Saskatchewan's Global Institute for Water Security. (Jason Warick/CBC)

"When we think about climate change, I think we can be expecting to experience more drought in the future," says James Famiglietti, a hydrologist with the University of Saskatchewan who has been studying global freshwater availability for over a decade.

"[Drought] will become the new normal."

But farmers have many tools to deal with this threat. From water reservoirs to drought-resistant crops, farmers the world over are practising various adaptation measures to remain viable.

Cover cropping

According to Kernaleguen, just a few years ago, his crops would have probably failed in this year's scorching heat.

Now, he's faring better than most Prairie farmers. He says that's in large part because he practises cover cropping.  

"It's these type of years that you can see the drastic difference," says Kernaleguen. 

Kernaleguen's fields stand waist-high, despite this year's scorching drought. (Submitted by Paul Kernaleguen)
Satellite images of Kernaleguen's farm in 2013 and 2019. Kernaleguen began cover cropping in 2014, and he says it has significantly improved his soil quality and crop yields over the years. (CBC News)

Cover cropping is a tool for farmers to manage soil and water quality, according to Yvonne Lawley, a professor in the department of plant science at the University of Manitoba who researches cover cropping.

"I think about cover crops as plants that we grow for reasons other than to grow food," said Lawley.

With the help of a few carefully selected plants, Kernaleguen engineered his land to be more resilient to the elements.

Before, his 260-hectare plot of land was home to barley and alfalfa monocultures, with only a single type of crop grown in a field at one time.

Now, most of his fields are a blend of different stalk lengths and leaf types.

Kernaleguen grows a mix of sweet clover, grasses, barley and faba beans in one of his fields. (Submitted by Paul Kernaleguen)

"What we've got here is a mix of cereals, pulses, peas, collard greens, clovers and also turnips," says Kernaleguen, pointing to one of his fields.

Kernaleguen holds a tillage radish, whose roots can break down dense layers of soil that block water from infiltrating. (Submitted by Paul Kernaleguen)

Each plant has different, but complementary root systems.

For example, cereals grow fibrous shallow roots that can absorb water quickly, while turnips grow deep tap roots that can harness subsoil water even in relatively dry conditions. Together, the different plants help the soil retain more water when it rains so that less is lost through runoff.

In combination with perennial crops and grasses that cover the ground year-round, Kernaleguen says he's doubled the organic matter in his soil.

Organic matter, a term which encompasses soil microbes, fungi, crop residues, manures, molecules from decomposed plants and much more, can drastically improve soil's hydration capacity.

"Having higher organic matter makes your field keep a greater amount of water," says Maryse Bourgault, a drought and agriculture researcher at the University of Saskatchewan.  

"So, if it doesn't rain, we have a bigger bucket that the crops can use."

Controlled traffic farming

Controlled traffic farming is the practice of keeping all farming equipment and machinery on the same tracks, year after year. 

Farm machinery can compact soil, leading to decreased water retention and poorer crop yields. (Dan Kitwood/Getty Images)

In Australia, where this management tool is widely used, farmers have experienced higher yields and better grain quality. 

"There's some data that shows that by not driving on soil, you're reducing that compaction," says Bourgault. "That means that your roots aerate the soil by themselves, allowing water to infiltrate."

A study in Alberta from 2014 to 2017 found the technique did increase soil quality and crop yield, but not as much as in Australia.

Peter Gamache, a retired farmer who led the project, said those benefits didn't justify the costs.

"It's not cheap because it means all of your equipment needs to be on the same compatible lengths," says Gamache. "It's not easy; it's a hard transition and a huge investment in infrastructure."

Creating water reservoirs

In places such as South America or China, rainwater harvesting has been widely practised for centuries to help address water shortages.

In the Canadian Prairies, water reservoirs are created by digging holes in the ground to access subsurface water. The reservoirs are further filled by capturing snowmelt during spring and by holding off water from small streams.

Stubble from harvested crops and cover cropping can help farmers trap snow on their fields during the winter. When the snow melts during spring, it provides water for the soil. (Dave Gilson/CBC)

"On the Prairies in Western Canada, we have tended to get our moisture from the winter and early spring period as we have a drier climate through summer and early fall," says Trevor Hadwen, an agroclimate specialist with Agriculture and Agri-Food Canada.

"We have a lot of very small local ponds or reservoirs that the provinces manage to help with water throughout the year. We're trying to capture the winter snowfall moisture in terms of runoff into those reservoirs so that we can use them during drier periods."

Overwintering crops

Bourgault suggests one way to avoid drought altogether is with overwintering crops. These crops are planted in the fall, and harvested by late spring to mid-summer — before the hot, dry weather kicks in.

Winter crops are planted in early fall and are allowed to overwinter. In spring, the crop grows quickly, taking advantage of early spring moisture and are ready to be harvested by mid-summer. (Kathleen Melnyk)

Kernaleguen grows winter crops such as winter wheat, hairy vetch, red clover, chicory and plantain. He says this year, they were some of his best-performing crops.

But so far, winter crops haven't been very popular among farmers. 

Maryse Bourgault is the Integrated Agronomy Research Chair at the University of Saskatchewan. She researches drought adaptation in semi-arid cropping areas. (Cristina Weese)

Bourgault believes this has to do with the farmers' timing of operations, because there is no ecological reason why winter varieties cannot be grown here. 

"I think farmers are used to the timing of spring wheat," says Bourgault. "If you're busy harvesting until late into September, then it's a little bit of an issue trying to get the planter out to plant something else."

Hadwen, on the other hand, says there is risk involved with planting winter crops. 

"You have to plant winter varieties at the right time and avoid frosts on both ends of the cycle," Hadwen says.

To irrigate or not to irrigate

The vast majority of farmland in Canada is rain-fed, according to Hadwen. Irrigation is not widespread, but it could help farmers in areas that are particularly dry.

irrigation on open field
The Saskatchewan government plans to expand agricultural irrigation, but many experts say the benefits are not guaranteed. (Don Somers/CBC)

Recently, the Saskatchewan government announced it will be spending $4 billion to irrigate up to 202,000 hectares of land from Lake Diefenbaker, more than doubling the irrigable land in Saskatchewan.

But Bourgault says irrigation is very difficult to properly manage and she worries it might degrade soil quality.

"[Irrigation] is really, really hard to do well," says Bourgault "We've had civilizations collapse because they couldn't get their irrigation under control."

Bourgault notes that irrigation water contains dissolved salts that can accumulate in the soil if there isn't enough drainage, rendering the land infertile for hundreds of years.

Chinese officials inspect salinized soil in northern China. It can take hundreds of years before soil with elevated salt content can be used for agriculture again. (Getty Images)

Hadwen fears the widespread expansion of irrigation in Canada will deplete water sources, reducing the amount of freshwater available for drinking and hygiene.

Drought-tolerant crops

Some solutions come from research labs. Bourgault is working on developing drought-resistant legumes and cereals for farmers.

She's found that plants with deep root systems and that flower earlier tend to do better.

Crops on farmland near Regina are showing signs of heat stress. (Kirk Fraser/CBC)

Hadwen says scientists with Agriculture and Agri-Food Canada are developing crops that consume less water by producing fewer leaves and stems.

He also says farmers can buy seeds that were bred to withstand longer periods of drought.

These seeds can be risky for farmers because they don't fare as well in wet conditions and climate researchers are still not able to accurately predict drought.

Adaptation is already succeeding

Ultimately, Bourgault feels positive about the future. She says Prairie farmers have already adapted considerably to dry conditions, and there are far fewer crop failures now than there have been in the past.

For example, the practices of reduced tilling and direct seeding in the Prairies is a direct result of past drought adaptation. Both of these practices reduce the loss of organic matter in the soil and thus help with increased water retention.

The objective on Kernaleuguen's farm is to keep something green and growing on crop and pasture land during as much of the year as possible. (Submitted by Paul Kernaleguen)

But Kernaleguen worries about his farm's future.

Although his fields are faring better than most in this summer's scorching heat, if you look closely, you'll notice his soil is cracking.

His crops have managed this year because of water stored deep in the soil from cover cropping, but he can only go so long without rain.

"Next year if you talk to me and we don't get any more rain, we might not look like that at all," says Kernaleguen.

ABOUT THE AUTHOR

Maya Lach-Aidelbaum is a reporter with CBC Yukon. She has previously worked with CBC News in Toronto and Montreal. You can reach her at [email protected]