Much of what we call the “Heartland” of the US was originally prairie ecosystems dominated by perennial grasses. During the era of “sodbusting,” these ecosystems were cut open and converted to annual grain production dominated today by wheat, corn, and soybeans. Tillage is intense, use of synthetic chemical fertilizers and pesticides is high, patented genetically modified seeds are most often used, and monocultures of these three crops dominate the land scape. Soil erosion, fertilizer runoff, biodiversity loss, the loss of family farms, the decline of rural communities, and farmland consolidation into bigger and bigger industrialized farms has become the model. Add climate change to this panorama, and the future looks grim indeed.
Agroecology provides one of the most effective and least expensive alternatives to this dilemma. Using agroecology to modify production practices and redesign farming systems to emulate nature’s own solutions for survival not only makes common sense but also contributes to resilience for future climate extremes and unpredictable events.
Many successful current innovations in the corn and soybean Heartland are based on ecological principles. No-till practices now common in lower rainfall areas of the Midwest provide a clear example of how minimal soil disturbance saves moisture, a critical factor for crops in drought-prone regions. The late Charlie Fenster, long-time Extension specialist in western Nebraska, confirmed that every tillage operation including planting can expose soil and result in loss of a half inch of precious moisture. He coined the term “ecofallow” where planting two crops in three years can intensify the traditional crop/fallow rotation and use water more efficiently. This pattern has been further intensified to two harvestable crops and a cover crop in three years, maintaining green crops, cover crops, and stubble on the land for continuous prevention of erosion and saving moisture. These provide a clear advantage to the wheat/fallow systems that only conserve about 25% of the fallow-year moisture, while the rest is transpired by weeds or evaporates from the soil surface.
At The Land Institute in Kansas, visionary Wes Jackson has spent five decades exploring and promoting “perennial polycultures,” planting mixtures of improved wild species of cereals and legumes that provide fertility to the system, manage unwanted species, and allow sequential harvests of compatible crops plus grazing for foraging ruminants. The systems build soil fertility, soil health, and provide continuous cover similar to the native prairie. Land Institute plant breeders have already selected several grain crops that produce a reasonable crop, while lifting water to supply the plant in dry years from soil strata with roots penetrating more than ten meters into the subsoil.
The current focus on soil health compels us to explore how plant species diversity in rooting patterns, nutrient use and time to maturity contribute to maintaining a diverse soil microbial community and enhanced nutrient cycling. These factors all contribute to resilience and long-term soil health without need for application of commercial fertilizer products.
In these ways, practices and systems informed by the natural prairie ecosystem contribute to soil fertility, weed management, and system stability. Agroecology encourages all these advantages, and helps the farmer reduce costs and introduce resilience in times of extreme and unpredictable weather events. Appreciation of these ideas is growing in the agricultural community, and presents opportunities for low-cost and effective design of future farming systems. This way we can bring the heart of the soil back to the Heartland.