What is in this article?:
- Soil is alive with organisms that convert air, water, organic matter and soil nutrients into a robust soil-plant system that can supplement and enhance seed, nutrient and crop protection technologies.
- Evaluate your soil-plant system as a synergistic, holistic system – not isolated tools of tillage, drainage and nutrient management. If you change or alter one tool, such as a transition to no-till, consider how to modify other factors for success.
- Rethink field management over an entire year, not simply in-crop. If corn-on-corn maximizes your economic opportunity, consider intercrop rotation with a cover crop.
- Create a long-term plan to improve and enhance soil conditions and track your progress.
Are you growing a crop for the next harvest or farming for the future?
Trend-setter advocates increasingly believe that a farming for the future philosophy is critical. Farmers who build a long-term base of soil health as the foundation for long-term profits will be miles ahead compared to simply growing next year's crop. Researchers, consultants and progressive farmers believe a more holistic, long-term approach is required to raise the bar on future productivity.
“In the past we talked more about the mechanical things – planting on time, adding the right nutrients and doing tillage and weed control correctly," says Bruce Erickson, agronomic education manager, American Society of Agronomy.” All those remain critical, but innovative farmers are increasingly concerned with the biological aspects of soils – areas we may not fully understand."
"The current approach is to apply control technologies to remove limitations – for example, fungicides and insecticides,” says Jerry Hatfield, plant physiologist and director, National Laboratory for Agriculture and the Environment, USDA-ARS, Ames, Iowa. “We have overlooked the role of a healthy soil on the biological components of the soil and how a healthy soil can offset the problems we think are occurring. “We have overlooked the value of soil biology in building a more robust soil-plant system."
NATURAL SOIL FERTILITY
Hatfield believes there is a need to look at the system and how it is fed from a more natural, biological fertility standpoint. "Let’s have the biological system do the work. We need to realize that soil biology requires feeding throughout the year and not just for short periods of time.”
Joe Nester works with innovative farmers in northwest Ohio, southern Michigan and northeastern Indiana who are doing just that. A former fertilizer plant manager, Nester has been working one-on-one with producers to improve management systems for nearly 20 years. Like Erickson, he sees a change in how they view these systems. “For years we said crop production had a chemical, physical and biological side, but we gave most of our attention to the chemical side,” he says. “That is changing, and the physical and biological sides are becoming more important. They take better management and outside-the-box thinking.”
Several factors are driving this new viewpoint. Hatfield cites the impact of yield monitors and precision agriculture that emphasize yield variations across a field and show how better soils offer more uniform yields from year to year. “We’ve been talking about the role of better soils on water availability and nutrient use efficiency for several years, and this is beginning to take hold,” he says.
Erickson warns that new challenges may emerge in the more automated system of crop production. “As we’ve reduced the production risks using seed treatments, better equipment, genetic engineering solutions for weeds and insects and more reliable genetics for emergence, and harvestability, our system has become more automated and prescriptive,” he says. “This has allowed farmers to manage other complexities such as farming more acres, or land spread over greater distances. But there is a danger when complex biological systems become simple in a manager's mind. Not all of our innovations will last forever, and new solutions may be needed to replace them.”
Sometimes those new solutions are old practices revisited, such as crop rotation. Others are newer practices revised, such as no-till and conservation tillage. Sometimes they are a combination of old and new, such as the rapid growth of between-season cover crops, especially in no-till cropping, and the resulting synergy. Although each of these practices initially appeared to resolve specific problems within the system, the confluence of them today points to a new understanding and appreciation for system-wide and long-term benefits.
The traditional benefits of crop rotation included market/product diversification, extended planting and harvesting windows and, in the case of legumes, added N. Commodity pricing has altered the market benefit in many areas, and bigger and more productive equipment has altered the importance of extended planting windows. Faster-emerging and more weather-tolerant seeds have further altered traditional planting cycles. In the case of weed and pest cycles, Erickson says the biotech solutions and other factors have altered the dynamics for many growers.
“The rotation question is influenced by many factors: input costs for each crop, such as seed, fertilizer, pesticides; what type of yields can be expected, influenced by soils, the farmer’s management, a crop’s position in the rotation; what prices one can expect for each crop, related to closeness to markets such as livestock, ethanol plants, rivers and railroads. These are different from region to region and from farmer to farmer.”
Fewer trips across the field combined with biotech-based weed control have made all levels of conservation tillage positive options. With increased attention to physical and biological aspects of the cropping system, new pieces join the calculation pie as soil health and structure are studied for incremental advantages in increased yields. However, it is that combination of no-till, crop rotation and cover crops that is really affecting soil health. In fact, Erickson compares adding a cover crop to adding a crop to the rotation.