SOURCE: Inside Climate News
DATE: January 25, 2019
SNIP: On his farm in southwestern Iowa, Seth Watkins plants several different crops and raises cattle.
He controls erosion and water pollution by leaving some land permanently covered in native grass. He grazes his cattle on pasture, and he sows cover crops to hold the fertile soil in place during the harsh Midwestern winters.
Watkins’ farm is a patchwork of diversity—and his fields mark it as an outlier.
But for several decades, ever-bigger and less-varied farms have overtaken diversified operations like his, replacing them with industrialized row crops or gigantic impoundments of cattle, hogs and chickens.
This trend is a central reason why American agriculture has failed to deal with climate change, a crisis that has been made worse by large-scale farming practices even as it afflicts farmers themselves.
The consolidation of American farming, reinforced by an emphasis on just one or two main crops—corn and soybeans—has led to a system in which there’s little incentive to grow much else, especially in the agricultural heartland of the Midwest.
This has profound climate and environmental implications. Mega-sized farming encourages practices that degrade the soil, waste fertilizer and mishandle manure, all of which directly increase emissions of greenhouse gases. At the same time, it discourages practices like “no-till” farming and crop rotation that grab carbon dioxide from the air, store it in the soil and improve soil health.
One recent government report called the trend toward ever-bigger farms “persistent, widespread and pronounced.”
“From a climate, soil health, and carbon sequestering perspective, we need greater diversity,” said Ferd Hoefner of the National Sustainable Agriculture Coalition. “We’re never going to make huge progress on soil health and carbon sequestration until we get that diversity.”
Hefty government subsidies, along with market forces and technology, have tilted the balance to corn and soybeans, transforming much of the Midwest into a vast duoculture of those two crops. The fields get bigger and bigger.
As ethanol mandates arrived, genetically modified “Roundup Ready” corn and soybeans had become the dominant crops in the country. Engineering these crops to withstand herbicides that kill weeds made them easier to grow across ever-bigger pieces of land.
While genetically modified crops simplified farming, they also boosted herbicide and fertilizer use. The Midwest became a nitrogen fertilizer hotspot, causing soils to emit more nitrous oxide, a potent greenhouse gas. The enriched runoff also feeds algal blooms, another source of greenhouse gases.
[Read the rest of this excellent in-depth investigation of industrial agriculture at Inside Climate News.]