Sustainable Partners

By John Pocock
Progressive Farmer Contributing Editor

Farmers active in a new, five-year initiative to improve soil health are becoming part detective, part economist, part environmentalist and part publicist, said Nick Goeser, soil health and sustainability manager, National Corn Growers Association (NCGA).

"We're trying to set up a demonstration network so that farmers can learn from other farmers what's working and what's not working in their individual efforts to adopt economically sound conservation practices," Goeser said. "The top three conservation practices that we're currently examining are cover crops, conservation tillage and prescription nutrient management."

The NCGA launched its Soil Health Partnership (SHP) initiative in February 2014, with support from Monsanto and The Walton Family Foundation, and technical advice from The Nature Conservancy, said Goeser, who is helping to administer the program. By year five (2019), they hope to have 100 farms signed up, he said. "The goal is for producers to have a place to view local conservation practices and talk with a peer on best ways to implement those practices."

Twenty farmers signed up to participate and establish test plots in 2014, and another 15 have committed to participate in 2015, Goeser reports. The large, field-scale treatments compare a conservation practice side by side with a farmer's normal practice. The cover crops being examined vary by geography, but for now, they are mostly cereal rye, oilseed radish, oats and clovers.

Initially, the SHP program will target the Midwest, particularly Iowa, Illinois and Indiana, Goeser explains. However, there are already participants from Nebraska, Ohio and Wisconsin. "So, there is the potential to expand beyond the Mississippi River Basin," he said.

MICROBIAL ADVANTAGE?

Tim Smith, Eagle Grove, Iowa, is one participating SHP farmer who's seen good success from planting a cereal rye cover crop. Still, he wants to improve on what he's learned.

"The organic matter levels in our soils are already pretty good, but we want to see if they can be improved, along with water infiltration, over time," said Smith, who grows corn and soybeans about 100 miles north of Des Moines. "There are unseen things we want to examine, as well, such as the microbial life that feed on our cover crops and how they interact to potentially increase yields for our row crops."

With help from the SHP initiative, Smith said he will be testing soils beyond standard fertilizer levels. "We're just at ground zero with the whole program, because we don't have a lot of data yet," he said. However, Smith points out both Rick Haney, with the USDA Agricultural Research Service lab, in Temple, Texas, and Cornell University have new soil-health tests that measure more than nitrogen (N), phosphorus (P) and potassium (K) levels. The cost is $50 to $70 per sample, but the test gives you a better picture of the microbial action in the soil than a standard soil test.

For now, N sequestration is the main benefit Smith cites with cover crops. "During my first year of seeding cereal rye, we had good growth through the spring in 2012," he said. "We harvested 1-foot squares, and we weighed out samples. We found the rye provided 810 pounds of biomass per acre. The samples were analyzed in a lab, which determined that 30 pounds of N were being sequestered in that biomass. That means more N stayed in my fields and didn't go through my tile lines and out into a stream."

In 2012 and 2013, the Iowa Soybean Association sampled water going through Smith's tile lines and in the stream above where his tile lines flowed. "They found the nitrate levels in my tile lines were lower than in the stream water," he said. "I attribute that result to using cover crops and spring N applications."

COVER CROP CONFIRMATION

Chase Brown, Decatur, Ill., is another farmer participating in SHP who has also already seen good benefits from growing cover crops. During the drought of 2012, the Brown family started growing a cover crop mix after wheat to feed livestock.

"We're about the only ones in our county that grow wheat to any extent," said Brown, who also grows corn and soybeans, and raises about 30 brood cows in a cow/calf operation with his father, David, and uncle, Joe. "We started out growing wheat for use with our livestock, but we feel a cover crop following wheat is giving us a better economic value than a double-crop with soybeans."

The central Illinois farm family is looking for ways to earn more income per acre than just growing corn and soybeans alone. "Livestock adds more value to our operation, especially by adding the cover crop," Brown reports. "We bale the cover crop for hay, chop it for silage or graze it. So, cover crops and cattle go hand in hand."

Currently, his family's operation is comparing cover crop treatments over 80 acres. On 30 acres, they have 120-foot strips of cover crops with no-till or minimum tillage that alternate with 120-foot strips of conventionally tilled strips with no cover crops. The conventional strips are tilled with a deep chisel and a vertical tillage tool in the fall, and then with a field cultivator in the spring.

On the other 50 acres, the farm has a solid cover-crop stand. The family is raising wheat, harvesting it and sowing the cover crop, which is a mixture of clover, radishes, sudangrass and some leftover soybean seed, Brown said. "These flat, black soils seem to respond to being fractured to get more water moving through them," he notes. "However, we're leaving a pretty big carbon footprint by running so much steel over the ground. We want to see if cover crops and minimum tillage will be a good, economic alternative to conventional tillage operations here."

Cover crops are "the new, big thing in agriculture right now," Brown said. "There are a lot of claims about the wonders of cover crops," he said. "I want to believe the claims are true, but I also want to do our due diligence to confirm or refute the claims. To do that, we need help to gather more information and to spread the word on the research that is being done."

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