Study: Ethanol push is a problem for butterflies

Source: Marc Heller, E&E News reporter • Posted: Friday, March 8, 2019

Nearly one-fifth of the Upper Midwest’s milkweed plants — the main staple in the diet of monarch butterflies — were lost from 2008 to 2016 as farmers converted land to crops for ethanol, the National Wildlife Federation said today.

In a report on environmental impacts of the federal renewable fuel standard, the NWF pointed to loss of milkweed as one of the impacts of ethanol’s rapid growth. Around 223 million milkweed stems have been lost on the butterflies’ migration route, and 17 percent in the Upper Midwest, the NWF said.

“There is no dispute that U.S. biofuels policy is driving environmental harm,” said Aaron Smith, a professor of agricultural and resource economics at the University of California, Davis, who joined the NWF on a conference call with reporters.

The group said its updated research also shed more light on conversion of grasslands to corn, including the application of an additional 300,000 tons of chemical fertilizer to support crops since the updated version of the RFS was enacted in 2007.

“The renewable fuel standard created a strong economic incentive to increase domestic corn production to meet the federal mandate for new biofuels. The ensuing expansion and intensification of crop agriculture has transformed the landscape, leading to a cascade of negative impacts on wildlife habitat, water resources and the climate,” Smith said.

The report said farmers converted 10 million acres to cropland from 2008 to 2016. Of that amount, the group said, 1.6 million acres of planting on new land could be tied to higher crop prices caused by biofuel growth from 2009 to 2016.

Farmers kept about 1.2 million acres in crop production rather than setting it aside in conservation programs due to higher crop prices, the group said, meaning cropland expansion during those years was 73 percent larger than it would have been without the policy.

The RFS sets minimum volumes of biofuel to be blended into the nation’s fuel supply. EPA is reviewing several aspects of the program, including a potential reset of volume requirements. The NWF and some other environmental groups, as well as the petroleum industry, have said the timing is right to reduce the volumes.

Ethanol industry and farm groups counter that the policy is meeting its purpose of reducing reliance on foreign oil and supporting rural communities. Criticism about land use overlooks the conversion of land from one crop to another — rather than from prairie — and the increased corn yields that require less land to harvest the same amount.

In addition, the use of ethanol has avoided greenhouse gas emissions that would otherwise have come from other fuel sources, and levels of particulate matter, carbon monoxide pollution and ground-level ozone have fallen since the adoption of the RFS, the Renewable Fuels Association said.

The study should be a “wake-up call to EPA and Congress” to scale back the mandate and revamp the RFS to boost biofuels other than corn-based ethanol, Collin O’Mara, president and chief executive officer of the NWF, said on the conference call.

While the RFS has sparked complaints from the petroleum industry and oil refiners that have to meet renewable fuel costs, O’Mara said, the environmental questions have broader impacts. “What about the cost of the program to the rest of us?” he asked.