Last year was a “bumper” year for corn production in the U.S., as American farms harvested nearly 14 billion bushels, enough to fill a freight train longer than the Earth’s circumference. However, “climate change, unsustainable water use, and inefficient and damaging fertilizer practices” pose a real and present threat to the long-term productivity of U.S. corn production — threats that ripple through U.S. corn’s extensive and vital supply chain, according to a new report from Ceres.
Nearly doubling in size over the past 20 years to yield $67 billion a year in revenue, corn is America’s biggest and most important crop. Nearly one-third of U.S. farmland — an area equivalent to two Floridas – is being used to grow corn. This is far more than the second and third largest U.S. crops, wheat and soy. In addition, U.S. farmers grow, harvest and export more corn than their counterparts anywhere in the world. That’s the good news.
Last year’s record corn harvest — and the corn industry’s growth over the past two decades — masks serious, and growing, threats from climate change, inefficient water use and over-reliance on fertilizers, Ceres report authors highlight in Water & Climate Risks Facing U.S. Corn Production.
Impacts across corn’s trillion-dollar value chain
The impacts and risks posed by corn as it’s produced today in the U.S. are felt well beyond the crop’s extensive, trillion-dollar supply chain. According to Ceres:
“In 2013, the top 45 companies in the corn value chain earned $1.7 trillion in revenue, which is more than the annual GDP of Australia.”
Overall, researchers found that 16 separate sectors – from fast food companies to fertilizer manufacturers to grocery retailers – depend on U.S. corn as a key ingredient for their products, or as a market for their inputs and services.
The environmental damage and threats resulting from corn production extend from U.S. waterways to the Gulf of Mexico, where fertilizer runoff has created one of the world’s largest marine “dead zones.” Corn production as practiced today also poses threats to soil fertility and volume, as well as a being a big contributor of the greenhouse gas emissions that are pushing climate past a critical tipping point.
Of corn, climate change, water and fertilizer use
For all the corn that’s produced in the U.S., the vast bulk of it isn’t consumed directly by humans. Just 10 percent of last year’s corn harvest went to direct human consumption, Ceres notes in its report. Almost 75 percent wound up in animal feed or was used to produce ethanol to fuel vehicles.
As spelled out in the third, recently released U.S. National Climate Assessment, variability in weather across the U.S. is increasing, as is the frequency and intensity of extreme weather events, which heightens the risks to agricultural production. Adding to this in 2014 is an anticipated El Nino event in the Pacific.
Evidence of what can be expected: The drought that hit the Midwest in 2012 drove the price of a bushel of corn up to a record-high $8. California, where farms produce most of America’s fruits, nuts and vegetables, is in its third year of severe drought. As a result, prices of a wide variety of common grocery items are rising sharply.
Extreme weather events hit hard and fast, as do their effects. In that, they provide a shock and offer something of a wake-up call on climate change. Compounding these risks are the inter-related issues of inefficient water use and over-reliance on fertilizers.
Corn, irrigation, aquifers and runoff
Growing water demand for irrigation and “unchecked” groundwater withdrawals for corn production are a double whammy that’s increasing the pressure on already stressed water sources, “in particular, the High Plains aquifer that spans eight Great Plains states and California’s over-extended Central Valley aquifer,” Ceres highlights in the report’s executive summary.
Another longstanding and growing threat results from farmers’ over-reliance on fertilizers to boost crop yields. Most of those chemical fertilizers wind up traveling into and through waterways, which has lead to the creation of the Gulf of Mexico “dead zone.”
Ceres found that 87 percent of irrigated corn production takes place in water-stressed regions. As the report authors point out, “[C]orn growers in the Mississippi River Basin lost nearly half a billion dollars-worth of fertilizer in 2013 due to agricultural run-off into the Gulf of Mexico’s ‘dead zone.’”
Among Ceres’ researchers other key findings:
- Over half of the country’s irrigated corn production, worth nearly $9 billion annually, depends on groundwater from the over-exploited High Plains aquifer, which extends from South Dakota to Texas;
- 87 percent of irrigated corn is grown in regions with high or extremely high water stress, meaning there is limited additional water available for expansion of crop irrigation. Many of these same regions can also expect worsening water shortages due to climate change. Corn-growing areas in Nebraska, Kansas, California, Colorado and Texas are the most vulnerable;
- $2.5 billion of corn grain is grown in 20 counties over portions of the High Plains aquifer where groundwater levels are rapidly declining. Five counties in particular have over $150 million each in annual corn grain production at risk from groundwater depletion: Yuma County in Colorado, and York, Hamilton, Adams and Filmore counties in Nebraska;
- 36 ethanol refineries are located in and source corn irrigated with water from the High Plains aquifer. Of these, 12 refineries, with an ethanol production capacity worth nearly $1.7 billion a year, are in areas where aquifer water levels are dropping.
- Inefficient fertilizer use in 2013 cost growers $420 million from run-off into the Mississippi River, and eventually the Gulf of Mexico. (Nitrate pollution due to fertilizer use by agriculture also costs water utilities $1.7 billion a year according to the USDA.)
- 60 corn ethanol refineries with $8.8 billion in annual production capacity are sourcing corn from watersheds with high local nitrogen pollution from agriculture.
Commenting on the research results, report author and Ceres Water Program director Brooke Barton, said:
“Escalating corn production for our food, livestock and energy industries has put the corn sector on an unsustainable path, especially in regard to water quality and water use impacts and the growing ripples from climate change. Corn buyers have an important role in recognizing this challenge and it’s encouraging that some are already trying to influence agricultural practices. Still, much more action is needed.”
Added Bridget Scanlon, a groundwater specialist who leads the University of Texas’s Sustainable Water Resources Program, “No doubt, groundwater resources are being strained by corn production, especially in Kansas and my home state Texas, which face extraordinary groundwater depletion challenges.
“The U.S. corn sector needs to greatly reduce its dependence on the High Plains aquifer. Failing to do so will have long-term negative consequences, including reduced agricultural productivity and less water for other uses.”
Corn buyers advocating for sustainability
Advocating for the development of sustainable business solutions for more than 25 years, Ceres represents a broad-based coalition of institutional investors, businesses and public interest groups. Leading an effort to enhance the sustainability and resilience of U.S. corn production is one aspect of “Valuing Every Drop,” a broader effort to enhance water conservation, sustainability and shared, responsible use, as well as Ceres’ climate change and other issues-driven sustainability work.
According to Ceres:
“[A] growing number of food and retail companies that rely on corn are developing supply chain initiatives to encourage more resilient and sustainable agricultural production in the sector, which has nearly doubled in size in the past two decades.”
In support of these corporate sustainability efforts, Ceres’ report authors offer the following recommendations regarding their corn purchases and relationship with producers and distributors:
- Setting a corporate policy with time-bound goals for sourcing agricultural ingredients (including corn) that are grown more sustainably;
- Integrating requirements for more sustainable agricultural production into supplier codes and procurement contracts;
- Supporting corn growers to adjust farming practices by providing direct agronomic assistance, performance guarantees and credit, as well as financial support to local and regional organizations that assist farmers;
- Supporting federal and state government policies that address climate change and encourage risk-reducing, environmentally beneficial farming practices and water stewardship.
As GNP Co. Sustainability Manager Paul Helgeson explained: “A critical factor for improving the environmental performance of production agriculture is to get the individuals managing the land, the farmers themselves, to see that environmental stewardship enhances profitability and is crucial to the long term viability of modern agriculture.”
*Images credit: 1) Grant Wood, “American Gothic,” via Wikipedia. All others: Ceres