I have learned more from observing Nature than by trying to change it,” said Dwayne Beck.
Beck, the research manager at Dakota Lakes Research Farm (DLRF) in Pierre, South Dakota, spoke at the Canadian Forage and Grassland Association conference.
Why it matters: Learning how to manage for better soil health is critical for future generations to farm.
In the 1990s, Beck travelled to Argentina where they were doing seven years of cropping followed by seven years of pasture system with diverse crop rotations and cover crops.
He was amazed by the health, structure and how rich the soil was while using almost no fertilizer. After the government changed the laws to encourage more soybean production and less livestock production, the same location a decade later already showed a vast degree of degradation within the soil structure and quality.
“The soils we have in a lot of the prairies were developed from these massive root systems of the perennials,” he said. “We cannot mimic that with annuals alone, we need to be using perennials in our systems. It makes a big difference to yield.”
Using complex systems
The DLRF has been incorporating nature’s system as a baseline to manage the ecosystem processes such as water cycles, energy flows, mineral cycles and community dynamics for decades.
“We need to address the problem instead of treating the symptom,” Beck said, using the example of terraces and waterways used to deal with erosion or water run-off issues.
Beck said natural systems take advantage of vesicular-arbuscular mycorrhizal (VAM) fungi webs, which are non-pathogenic micro-organisms with the ability to boost water and nutrient uptake, especially in poor, arid soils and protect the plant against root pathogens.
Ecosystems that leak nutrients turn into deserts, said Beck. When settlers arrived in the lush lands of South Dakota in 1889 they likely didn’t anticipate that within 50 years they’d be dealing with the Dust Bowl of the 1930s.
“A reduction in pH, organic matter and fertility are a symptom of poor nutrient and water cycle management,” said Beck.
Weeds and disease, to some extent, are nature’s way of reintroducing diversity into a system that lacks it.
“Mother Nature is an opportunist. If you provide the opportunity, she will take advantage,” he said.
Soil-water interaction is critical
For example, a small amount of organic matter by weight has a big impact on pore space because it only weighs one-fifth as much for the same volume.
“Within all textural groups, as organic matter increased from one to three per cent, the available water capacity approximately doubled,” said Beck. “When organic matter content increased to four per cent it then accounts for more than 60 per cent of the total (available water capacity).”
Beck said increasing available water capacity is key to not only getting through dry periods but also wet periods when soil is capable of absorbing vast quantities of precipitation or melt.
In a three-year DLRF project looking at the rotation impact on winter wheat using corn-pea winter wheat, one plot with high residue crop and the other with high and low residue crops the high residue not only provided nearly double the yield, it didn’t matter if it was a dry year or a wet one.
“Even in the wet year when we had 600 millimetres of rain, we almost doubled the yields,” said Beck. “We’ve now changed that low residue sequence to contain a perennial grass.”
Grazing animals complement dry, cool environments
In an effort to mimic Mother Nature, Beck said they looked at the impact of grazing animals.
In brittle, or dry climates, soil biology slows to a great extent with low soil moisture, however, the rumen of grazing animals remain moist continuing the biological processes.
In colder Canadian climes, soil biology slows with lower soil temperature, said Beck, but the rumen of grazing animals remains warm during those periods, continuing the biological processes.
“We think one of the real keys to ramp up biological processes is to include animals in the system,” he said.
Beck said the only way to produce human-edible protein on marginal land is to use a ruminant animal, which in his opinion could require upward of 40 million more cows, goats and sheep.
“The idea of producing meat in a laboratory using plants that are grown on farmland does not fit marginal land,” he said. “So we take the marginal land out of the equation in terms of producing human edible food. This is one of those things we need to do more education on.”
Beck said as long as government and corporations, which are focused on short-term, election-to-election goals, set the priorities the symptoms will remain and the solutions will be elusive.
“We use 600 years as one of our parameters at Dakota Lakes, ‘What’s going to happen in 600 years if we continue to do this?’”
Education is needed to show that doing the right thing environmentally is almost always the correct economic approach in the long run, he said.
Beck’s said agriculture must learn to do the right things better. At the research farm, that includes attempting to reduce the farm’s reliance on fossil fuels.
“The Dakota Lakes Research Farm’s board of directors had made it a goal to be fossil fuel neutral by 2026,” he said.
The farm presses its own oilseed, canola, flax, sunflower and soybean, using or selling the oil to offset fossil fuel purchases, while up-scaling the meal to supplement feed.
Beck said, in reality, the time for transformational change was 600 years ago before we started degrading the ecosystem, because most last 500 years.