When it comes to managing farming systems, too often the agriculture industry gets hung up on single components of the system at the expense of long-term thinking, says a researcher.
“I liken this to driving down the highway, looking at the edge of the ditch to try to keep from going in the ditch. It works in a blizzard. It’s not a good way to run a farming operation,” says Dr. Dwayne Beck.
“Can we look down the road and say where do we want to be, and can we do better and start managing? And one of the ways to do that is diversity.”
Beck is the research manager at the farmer-owned Dakota Lakes Research Farm in South Dakota. In 2007, he was inducted into the South Dakota Hall of Fame for his work developing more efficient and environmentally-friendly farming systems.
The research farm has been no-till for decades. But Beck doesn’t see zero tillage as the end goal.
“The zero till thing doesn’t work very well here because they haven’t added in diversity here. In fact, they used it to take diversity out.”
Diversity is good insurance
“The way we deal with drought is by having diversity. We have some crops that do really well when you have a dry year and some crops that don’t do so well,” says Beck.
“And then if you have diversity when you get a wet year, you have some crops — different ones — that do well and some that don’t do so well.”
“So on average you have a lot of resiliency by having this diversity in the system, both in crops that you grow and in how you position the crops.”
In 2012, the research farm’s winter wheat averaged nearly 100 bushels per acre on the good soil, and over 90 bu./ac. on the poorer soils. Sorghum yielded about 80 bu./ac.
Other parts of the rotation are meant to take advantage of wet or normal years. Dryland corn planted into soybean residue failed during last year’s drought. But Beck says in 2011, the corn yielded 140 bu./ac., so it averages out in the long-term.
Diversity sustainable in the long-run
Beck says that doing the right thing environmentally is almost always the correct economic approach in the long run.
Energy inputs account for 80 per cent of total inputs in most farming operations today, Becky says. Nitrogen eats up a huge part of the energy inputs on a typical farm. Beck says it takes the energy of one gallon of disease fuel to manufacture and transport five pounds of nitrogen. Applying 150 pounds per acre of nitrogen is equivalent to 30 gallons of diesel fuel.
“Human beings are incredibly good at just coming in and totally using our resources and leaving and running out and then starting to scramble. At Dakota Lakes, we’re starting to scramble early.”
Beck and his colleagues still apply some fertilizers. For example, they apply starter phosphorus with the seed. Other nutrients will be side-banded. Some nutrients are applied after wheat has emerged to prevent tillering. Beck says broadcasting fertilizer before or during seeding feeds weeds.
Beck likes to grow cover and forage crops to use water, increase organic matter, and capture nutrients such as carbon and nitrogen. Perennial grasses and alfalfa pull nutrients from further down in the soil profile, making them available for the next crop. Beck also integrates livestock into cropping systems to cycle nutrients back onto the land.
“The best biomass digester has four legs and goes moo,” says Beck.
The short growing season is a challenge for Canadian farmers. Beck says part of the secret is to spread the workload by growing crops like winter wheat. Perennial cover crops are also something farmers should look at, Beck says.
Beck’s research shows growing corn bumped wheat yields by 10 to 12 per cent. Warm season grasses like corn build organic matter, fix carbon, and use water efficiently. Corn is seeded later, allowing farmers to use different herbicides for pre-seeding burndowns.
Farmers can only grow so many acres of canola well, Beck says, so it may be worth investing in corn variety research for Canadian farmers.
Stacked rotations involve growing the same crop two years in a row in the same field, followed by a four year break.
“The real reason for doing this is to have a long break. And it’s hard with the limited number of crops we grow to have a long break.”
The long break reduces disease by cutting inoculums. Wet weather in the first year might allow inoculums to build up. But the second year would need to be wet as well for disease to break out, which is uncommon in Beck’s area. Growing the same crop a third year would be much higher risk, though, so Beck switches crops in the third year.
Stacked rotations also keep pests and weeds from gaining a hold in farming systems. They allow farmers to use herbicides with long residual times, and use less herbicide, Beck says. Pests will take advantage of regular patterns, such as two-year rotations. Mixing up crop sequences and intervals keeps them guessing.
For example, corn rootworms usually lay their eggs at the base of the corn plant. If farmers plant corn the next year, the larvae eat the roots. To get around this, farmers started rotating corn with soybeans.
“In the western corn belt they developed a type of rootworm that we call extended diapause, where the eggs don’t hatch for two years,” says Beck. “In the eastern corn belt they developed the soybean variant, where the pregnant females flew to the soybean fields to lay their eggs.”
Beck says at the main research station, they haven’t used insecticides for eight or nine years. They haven’t used a grass control herbicide in wheat since 1990.
Beck’s goal with rotations is to mimic native prairie ecosystems. He says to even come close to managing soil the way native prairie does, farmers need to add more grasses into rotations. Including high-residue crops in rotations, and keeping that residue on the field, also adds more nutrients and organic matter.
But Beck says he can’t tell a farmer which specific rotation will work best for an operation. “But if ever you get a disease or weed issue, it means that you allowed the opportunity for those.”
The trick to controlling diseases and weeds is removing that opportunity, Beck says.
“To be real honest with you, there’s just not enough chemistry available in the world to kill everything that’s out there. You can’t do that. I mean, if you did kill everything that’s out there, you’d have this sterile thing that wouldn’t grow anything.”
For more information on Beck’s research, visit www.dakotalakes.com. †