Katy Dynarski - - Soil Health

The Business Case for Building Soil Health

Healthy soils are key to sustaining plant life. While intuition suggests building soil health should be beneficial for both farmers’ land and wallets, the economic benefits hadn’t been quantified until recently. How can healthy soils contribute to farm profits?

In a series of case studies recently published by the National Association of Conservation Districts (NACD), researchers aim to quantify the economic benefits of managing for soil health. In the study, corn-soybean farmers in the Midwestern United States experimented with soil health conservation practices like reducing tillage and planting cover crops. The results saw a trend: over the three-year period of the study, farmers saw their net income grow by as much as $110 per acre compared to their baseline.

Healthy soils store nutrients critical for crop growth, reducing the amount of fertilizer that farmers need to apply. Healthy soils also experience less compaction, runoff, and erosion damage, so costs of erosion repair drop. Thanks to improvement in nutrient and water storage, as well as increased biodiversity in the soil ecosystem, crops also tend to grow better in healthier soils. All of this translates to both increases in yield and reduced cost in fertilizer application and erosion repair.

Healthy Soils Cut Fertilizer Costs

In the early 1990s, Stan Kuhns grew concerned about soil conditions on his family’s 1,800 acre corn-soybean farm in Effingham, Illinois. In hopes of improving soil quality and saving money on his labor and machine costs, he switched to a no-till practice. No-till agriculture decreases physical disturbance to the soil, allowing soil to develop better structure and maintain more organic matter. This can lead to a decrease in runoff and erosion issues, and allow soils to store more water and organic nutrients to support crop growth.

Within a few years, organic matter rich in nitrogen and phosphorus began to build up in his farm’s soil, reducing the amount of fertilizer that he needed to apply. Kuhns also switched to more precise fertilizer application techniques, resulting in further decreases in fertilizer costs. After just a few years, fertilizer expenditures plummeted, saving Kuhns almost $50 per acre, according to the budget analysis in the NACD study.

Healthier soils are also better at retaining externally applied fertilizers. On Michael Willis’s farm in Missouri, he was able to apply less fertilizer after a few years of planting cover crops, and he noted that the cover crops “helped keep what fertilizer I did apply in the field, rather than letting it erode away.”

"After just a few years, fertilizer expenditures plummeted, saving Kuhns almost $50 per acre."

Healthy Soils Erode Less

When Dan Diaz took over his family’s farm in northern Illinois in 2005, he noticed that soil erosion was a widespread problem. He began experimenting with cover crops like cereal rye and tillage radish.

“I was hoping to build the soil back up, utilizing the rye to slow water movement and trap soil in previously eroded areas,” Diaz explained. The experiment paid off, and he saw that his fields with cover crops were visibly less compacted than his other fields after just one year. “The annual rye grass and the radishes broke the compaction up, and they allowed the soil to drain better and dry out more effectively,” he observed. That year, Diaz saved 20 percent on erosion-related repairs for his fields with cover crops.

Other farmers saw similar results from both no-till and cover crops, and across the four farms that participated in the NACD study, erosion-related savings amounted to $16 per acre.

Healthy Soils Boost Yields

Because they retain more nutrients, store water more effectively, and have more biological activity, healthy soils provide a better environment for crop growth than degraded soils. This can translate to dramatic yield improvements. Almost all of the farms in the NACD study reported increased crop yields, resulting in an economic boost of as much as $76 per acre.

Improving soil health can also help maintain yields when environmental conditions are less than ideal. On his Iowa farm, Frank Moore found that his soybeans were more resilient against disease after three years of incorporating cover crops, leading to a yield increase of 20 bushels per acre during the last year of the study, even though his neighbors’ soybeans were falling victim to white mold.

On the Kuhns farm, which has now been practicing no-till for 23 years, Stan Kuhns has noticed that their yields stay high even during drought years. Kuhns suspects this is connected to the improvement in soil water storage. “You have a reservoir of moisture…if you get a stressful year, that’s when organic matter and no-till make the difference,” he explained.

"If you get a stressful year, that’s when organic matter and no-till make the difference.”

Experimenting With Soil Health

While the NACD case studies focused on farms using no-till and cover crops, these are not the only techniques to build healthy soils. Additional strategies include applying compost to fields, increasing the diversity of crop rotation, precision fertilizer application, and implementing micro-irrigation systems.

With more innovations in ag-tech in recent years, it’s becoming easier than ever for growers to efficiently test out and optimize practices to build soil health. Advances in planting, fertilization, and irrigation technology can improve on-farm efficiency and reduce inputs of water and fertilizer to soil, saving time and money while contributing to soil health. And real-time feedback on soil quality from innovations such as wireless soil sensors can provide crucial data for experimenting with new management practices or honing the precision of currently-used ones.

For growers thinking about adopting new management practices, Kuhns recommends working with a local university extension specialist. “They have done a lot of research and have sound advice to help the transition,” he suggested.

An extension specialist can also help to identify incentive and cost-sharing programs to help offset the costs of starting experimenting with a new technique. These programs, like the National Resource Conservation Service Environmental Quality Incentives Program, can provide both financial and technical support for farmers implementing soil conservation practices, and ease the economic risk of trying something new on the farm.

No matter what the method of building soil health, the farmers in this study recommend starting small, and being willing to experiment and find what works best for your farm. “Start small enough so that it doesn’t freak you out, but large enough to matter,” advised Willis.

Though adopting new strategies required an initial investment of time and money, the farmers participating in this study all saw sizable economic returns as they worked to grow their soils in addition to their crops. Best of all, the benefits of these healthy soils have only increased over time. “I’ve been producing higher yields on the same soils for almost 25 years, and my soils continue to improve,” grinned Kuhns.