Tar spot fungus is a new reason to stay on your corn-scouting toes, especially if you’re in the central Corn Belt. It was first found in northern Illinois and Indiana in 2015 before spreading to 12 other states and one Canadian province. Corn yield losses range from 20 to 60 bu/ac, and tar spot can also trigger complications such as lodging.

Beneficial soil microbes, such as arbuscular mycorrhizae fungi, extend nutrient and water absorption of roots, and build soil aggregates. The soils beneath your feet harbor a powerful secret. Naturally occurring microbes called arbuscular mycorrhizal fungi (AMF) live among roots, releasing tightly bound nutrients into plant-available form.

Kernza farmer Carmen Fernholz says deep roots are the “wisdom” of perennial crops, as their long life spans help build large root systems. He promotes perennial grain crops’ erosion control and their little to no need for inputs. “Most food crops are annuals, requiring far more water, fertilizer and energy than perennial crops," Fernholz says. “Soil’s built from the roots up, rather than from aboveground,” he says, explaining why he has perennial Kernza and alfalfa in his small-grains rotation. Perennials’ long life spans build large root systems, accessing soil nutrients and water not available to annuals’ smaller and more temporary roots.

Soil microbes are what have built soil highways for efficient transport and storage of soil moisture, gases and nutrients. "Soil microorganisms decay organic matter and cycle nutrients back into forms that plants can use,” says Jill Clapperton, rhizosphere (root zone) ecologist and president of Rhizoterra, Lolo, Mont.

Most insects are benign or even beneficial for farming. Beneficial insects work almost invisibly, helping farmers grow crops. For example, pollinators are beneficial insects, but aren’t the only helpers. Many of these insects require pollen or nectar at some point in their life cycle to survive periods of prey scarcity, to overwinter and/ or to enhance their reproductive success. Cash crops, especially grains, typically lack pollen early in the season. So, it’s helpful to have perennial blooming plants or cover crops (such as buckwheat, sweet alyssum, clovers, etc.) on idle land or marginal areas of a field to sustain them.

Jorgensen Land and Cattle, Ideal, S.D., raises the most cost-effective bushel, not the highest yield. It’s accomplished through an innovative agronomic system developed by Bryan Jorgensen that focuses on increasing soil health through crop rotation, no-till, cover crops and livestock to optimize every ranch resource. This prairie ecosystem efficiently recycles roots, crop residues and organic matter into carbon and nitrogen that feed crops. It also hones their cropland acres’ efficiency and profitability. Just as important to the operation’s business model, Nick Jorgensen (Bryan’s son) assigns dollar values to conservation practices. Math and spreadsheets document the return on investment of every incremental input addition—the point of diminishing returns for seeding rates, variable-rate fertilizer and maximum return to nitrogen at Jorgensen Land and Cattle. The MBA grad and enterprise CEO designed and implemented a whole-farm recordkeeping system tracking every operational aspect. It’s all designed to help measure and track soil health’s return on investment.

What can we learn from soybean yield contest winners? Larry Purcell, University of Arkansas, has some answers based on three years of document ing how Kip Cullers, Stark City, MO, grew 160.6-bu/ ac soybeans in 2010. This article addresses the controversy of adding nitrogen fertilizers to soybeans, as some yield contest winners are assumed to have done, and identifies some of Cullers’ important practices to increase yields and profits for more mainstream soybean growers. In addition, we examine the profitability of yield-increasing practices as verified by 60 site- years of data.

Data collection and analysis maximizes output per dollar invested. Seth Lawrence, Brook, Indiana, uses detailed field zone data tracking to assign the highest allocation per dollar of working capital. He makes profit maps instead of yield maps. He knows which agronomic practices and field zones are most profitable. His data-tracking technology manages equipment cost and identifies ROI on agronomic decisions. Input ROI by soil type or zone varies because some soils are more productive than others. This isn’t much different than how factory managers gauge different production variables like labor and material cost, although weather is more of a factor.

Farmer and engineer Clay Mitchell troubleshoots his crop yields the same way an engineer fine-tunes any process: He identifies yield variations and then fixes the cause. “The cause can include uneven nozzle and planter flows, poor implement guidance, ammonia/strip-till shank problems and residue distribution,” says the Buckingham, Iowa, farmer, Harvard biomedical engineer and ag technology whiz.

The type of clay you have in your soil could make a $10,000 or more difference in your potassium (K) availability. Groundbreaking research by North Dakota State University (NDSU) Extension Soil Specialist David Franzen and others reveals that a soil’s clay mineralogy is responsible for K fixation (tie-up in unavailable forms).

Greg Entinger, New Prague, Minnesota, gave himself a huge pay raise when he switched from conventional tillage to strip-till in 2015. The extra money in his pocket comes from fewer trips across fields, reduced fertilizer rates and selling off unneeded equipment. As a process engineer, Entinger’s day job was making food processors’ factories more efficient. Entinger challenged himself to streamline farming the same way he did in his day job. “I asked myself why I hadn’t applied new technologies to streamline farming the way I did at work,” he says. He now saves 155 hours of tractor time annually by strip-tilling corn and no-tilling soybeans compared to conventional till corn and soybeans. Over time, Entinger has cut P and K rates by 33 to 50%, as more active soil organisms and root mycorrhizae fungi make nutrients more plant-available. Soil microorganisms and mycorrhizae are known to thrive in undisturbed soils. In 2022, he’s considering cutting P and K rates to 25% of what they once were.

The invisible world of soil microbes beneath your feet convert sunlight, water, CO2 and crop residue into crop income, courtesy of the “most incredible zoo,” says Diana Wall, soil ecologist at Colorado State University. They are out of our sight, but too vital to ignore. When you apply phosphorus fertilizer, for example, the P may become chemically unavailable be- fore the plant can absorb it, and soil microbes make it available through the growing season by unlocking chemical bonds. Soil microbes are what have built soil highways for efficient transport and storage of soil mois- ture, gases and nutrients. These become more vital during floods and droughts. “Soil microorganisms decay organic matter and cycle nutrients back into forms that plants can use,” says Jill Clapperton, rhizosphere (root zone) ecologist and president of Rhizoterra, Lolo, Mont. Untilled soil has $2,600 worth of free crop nutrients per arable acre in the top 6 in., says soil microbiolo- gist Kris Nichols with the USDA-ARS Northern Great Plains Research Laboratory, Mandan, N.D. Soil carbon is the invisible plant and micro-organism fuel produced by photosynthesis that feeds the magic microbes that work for us un- derground. The bottom line, Nichols says, is that working with soil microorganisms improves their fuel efficiency to produce your crop. Just as you control weeds and fertilize soil to optimize field environment above ground, you can work with soil microorganisms underground to speed their conversion of residue into plant-available forms of N, P and other key nutrients. Your crop changes sunlight to fuel (soil carbon), which builds the machine (plant material and roots) that creates crops.

The micronutrient chloride (Cl–) is one of 17 essential nutrients for plant survival. Chloride deficiency can be an issue in wheat, barley, oat, corn, and grain sorghum. In other species, like soybeans and rice, too much chloride can hurt yields. Chloride is required for cell turgor, enzyme activation, nutrient transport, water and ion movement in cell vacuoles, and stomata regulation of plant moisture content. It even helps split water molecules to liberate oxygen during photosynthesis. Chloride deficiency is most common in Kansas, Montana, Wyoming, western North Dakota, and South Dakota where chloride soil levels can be naturally low and/ or where limited potash (KCl) was historically applied, until recently. Because chloride is the most leachable nutrient, you also see deficiencies in areas with high fall and winter precipitation.

“We’ve always expected $4 corn,” says Ken Rulon. “Our cost of production, including a return to our owned land, is $3.89 per bushel.” It would take a 30-bushel yield increase for Rulon Enterprises to cover the 15% higher operating cost of conventional tillage, he adds. Rulon Enterprises capitalizes on advanced, environmentally beneficial practices to build soil health and sustainable profits.

Increased soil carbon fuels higher crop returns with more nutrients retained and recycled. Loran Steinlage has a more permanent solution to heavy downpours than tile drain. He’s improving his soil structure. By increasing soil carbon he’s built resilient soil that drains well and stores water for droughts. His financial returns are highest on the fields with the most diverse cover crops, cash crops and relay crops. By “relay,” he means growing a second crop (soybeans, rye or wheat) in the same growing season. This diversified soil allows microbes to retain and recycle nutrients, stores nutrients and prevents erosion through winter while adding income from cover-crop seed. By comparison, a conventional crop rotation has a “brown winter season” vulnerable to nutrient and soil loss, and the death of beneficial soil microbes.

Bryan Jorgensen figures the early settlers were optimists to give his South Dakota hometown the name of Ideal. Native gumbo clays, 20 to 23 inches of annual rainfall and cold, wet springs aren't exactly ideal cropping conditions. Farming closer to the edge of profitability means Jorgensen Land and Cattle has to produce more with less than those who enjoy better soils and climates.