On a recent August evening in south-central North Dakota, soil scientist Kristine Nichols laid out what I like to call the “purebred vs. the plugger” approach to farming.
“With healthy soil, you may not out-yield your neighbor in the best years, but you will out perform them in the not-so-good years,” said Nichols, a soil microbiologist at the USDA’s Northern Great Plains Research Laboratory.
In other words, when the rains come at the right time in the right amounts, the land soaks up just the right amount of heat units and pests remain at bay, nothing in the world can outperform a high-strung, “purebred” field of corn fed a steady diet of chemical inputs. But when the weather and other environmental factors go sour, you better place your money on a “plugger” cropping system that’s reliable, if not outstanding.
That fact was reinforced this summer when the USDA and the Conservation Technology Information Center released the results of a farmer survey showing that cover crops—plantings of small grains and other species either right after harvest of a cash crop or while the cash crop is still growing—more than paid for themselves in the Upper Mississippi River watershed during the drought of 2012. Corn and soybeans planted in 2012 after cover crops had a 9.6 percent and 11.6 percent yield increase, respectively, when compared with fields that had no cover crops, according to the survey.
This is key, because while cover crops have proven themselves as sure-fire ways to increase the biological activity needed to improve soil health, many farmers have shied away from them because of concerns they will cut into maximizing yields of cash crops like corn and soybeans. But in these days of increasing extreme weather events like flash floods and flash droughts, “perfect” growing conditions required by purebreds are getting harder to find.
Reading about a survey supporting the agronomic viability of cover crops is one thing, seeing it firsthand is quite another. Nichols made her recent comments while standing on the edge of a thriving sunflower field that had been inter-seeded with 10 species of cover crops (buckwheat, flax, cowpea, turnips, etc.). Despite droughty conditions —officially 3.37 inches of rain fell on this particular field between June 16 and Sept. 1—the sunflowers were chest high, and the soil between the rows was covered in a riot of cover crop plant life.
Nichols was showing this field to a contingent of Minnesota farmers and soil experts who had just spent the day seeing what people in North Dakota’s Burleigh County were doing to develop the kind of soil that’s not just reliable, but resilient enough to produce profits in even the harshest conditions. This tour was sponsored by the Minnesota Natural Resources Conservation Service and the USDA’s Sustainable Agriculture Research and Education program. Over 40 participants came from across Minnesota to learn how farmers in Burleigh County are building soil health in a region that gets only 16 inches of precipitation annually—that’s a foot less than what Minnesota gets in a typical year.
As this blog described last week, during the past several years the Burleigh County Soil Health Team has used a combination of cover crops, rotational grazing and no-till farming to increase soil’s natural ability to build its own fertility, resist erosion and make better use of moisture. The Team, which consists of local farmers, NRCS experts, Soil Conservation District personnel and scientists from the Northern Great Plains Research Laboratory, has attracted attention from around the world.
The Minnesota contingent was impressed with what has been done in Burleigh County to build organic matter—a major engine of healthy soil—and thus reduce runoff, resulting in less erosion and a healthier water cycle. But a version of this particular question came up repeatedly during the tour: “How can we show this pays off financially?”
The farmers who hosted the tour had plenty of answers to that query, which is particularly pertinent at a time when inflated commodity prices and a broken federally subsidized crop insurance program are combining to make intense use of tillage and inputs—both highly damaging to soil health—quite lucrative.
One thing the Soil Health Team has found is that planting multiple species of cover crops—as many as eight, 10 or more in some cases—is not only good for the soil, but good for the bottom line. Farmer Jerry Doan showed the Minnesotans a shoulder-high stand of cover crops that included millet, a type of sunflower and grazing corn. He explained that this stand, which was planted June 20, will be grazed starting in November, providing winter feed for his beef herd. Doan estimated that in 2011 grazing cover crops produced $50,000 in savings for his operation and took pressure off his regular pastures.
“People say to me, ‘How can you afford to have that land out of production?’ To me, it’s not out of production. I had a goal that every acre of cropland on this place would be profitable,” said Doan, who has recently been joined in the farming operation by two sons. “Fifty thousand dollars when you’re bringing in another generation is another family income.”
Doan and other members of the Team insist that even if they are not grazed, cover crops pay off by building enough organic matter to reduce the need for expensive chemical inputs in the future.
Burleigh County farmer Gabe Brown has reported that raising organic matter on his farm has allowed him to reduce the use of commercial fertilizer by over 90 percent, and herbicides by 75 percent. At today’s fertilizer prices, each 1 percent of organic matter contains $751 worth of nitrogen, phosphorous, potassium, sulfur and carbon, he estimates. That means Brown’s 5 percent organic matter content is worth $3,775 per acre. Ohio State University estimates that each 1 percent of soil organic matter is worth $680 per acre—that’s not as high as Brown’s estimate, but it’s still an impressive financial boost provided by all those microbes we tend to take for granted.
One thing that became clear during the recent soil health tour in Burleigh County is that many of the farmers there see building soil health as an investment in long-term productivity, rather than a quick way to make a buck. Brown compares it to buying fertilizer ahead of the growing season before prices spike.
That’s why so many producers working with the Soil Health Health Team utilize techniques like mob grazing, which puts cattle onto a stand of cover crops for short, intense periods of time. Because the grazing period is so short, animals will not eat everything before they are moved to a different paddock, and that’s a good thing. That just means all the plants’ roots and uneaten stalks, along with the manure and urine produced by the grazing cattle, will feed billions of microbes below the surface of the field. Those microbes will go into building the soil’s health, which in turn will help produce next year’s corn, sunflower or wheat crop.
Seeing “wasted” biomass as actually an investment in the long-term viability of a field requires farmers to step out of the mindset of treating soil like a sterile, mechanical plant stand and more like the living, breathing ecosystem that it is. It also means taking a hard look at one’s ultimate goal: is it high yields or consistently profitable yields? There’s a difference—raising a 200-bushel corn crop may be impressive, but can be an economic bust once high dosages of inputs are included in production costs.
And as Jerry Doan’s comment about wanting every acre to be profitable makes clear, building soil health is about using that ecosystem efficiently. Douglas Miller, Minnesota’s NRCS soil health coordinator and one of the organizers of the North Dakota tour, compares the current conventional system of growing row crops a few months out of the year and leaving the soil bare (and thus shutting down biological activity) the rest of the time to a poorly run factory.
Miller asks, “What business model would allow their source of production to sit idle for seven months?”
Brian DeVore is the editor of the Land Stewardship Letter.