The Environmental Protection Agency recently called for public comments on whether and how the agency should regulate greenhouse gas emissions under the Clean Air Act. This is the first step in a process that could have sweeping negative consequences for America's farmers and ranchers.

What's the problem? Simply put, the Clean Air Act is not the means for regulating CO2 or greenhouse gasses. It is a rigid and inflexible law, and its use would bring about regulation under two EPA programs. This is the kind of regulatory burden farmers cannot afford.

Climate change specialists with Farm Bureau say the proposed rules are aimed at automobile greenhouse gas emissions, but the unintended consequences could result in many family farms being brought under that regulatory umbrella. The threshold for these programs is 250 tons per year of a pollutant being emitted. It is this 250 ton burden that will hit America's family farms hardest. A significant number of ag operations emit 250 tons of CO2 per year and would therefore fall under these programs. Currently, there are no agricultural facilities regulated under either program.

An even larger issue facing agriculture is the possible regulation of emissions from methane and nitrous oxides. Both are greenhouse gases that are more potent than CO2. Methane comes from livestock, and is 21 times more potent than CO2. Nitrous oxide is used as a fertilizer and is 310 times more potent.

The Clean Air Act is aimed at very serious and very scarce air pollutants from sources such as large chemical plants. It is not designed to regulate a dairy farm in Wisconsin or a cattle ranch in Texas.

The EPA request for public comment is in response to an April 2007 Supreme Court decision, Massachusetts vs. EPA, which found that greenhouse gas emissions could be regulated if EPA determines a cause or contribution to air pollution that endangers public health or welfare.

The Agriculture Department has come out against the proposed rules. In its objections, USDA said dairy farms with 25 cows, beef operations with more than 50 head of cattle, swine operations with more than 200 hogs and farms with more than 500 acres of corn, all could be brought into the regulatory fold if the rules are approved.

USDA predicted dire results for farmers if the proposed changes are implemented, such as higher input costs and regulatory burdens. Consumers will likely feel the pinch as well, due to higher food prices and reduced domestic food supplies.

The White House and EPA have also come out against regulating greenhouse gasses under the Clean Air Act. This should bode well for Farm Bureau and others working to ensure this scheme never sees the light of day. But it is still critical for farmers to speak up and submit comments to EPA urging that greenhouse gasses not be regulated under the Clean Air Act.

As President Bush said in a Rose Garden speech earlier this year, there is "a right way and a wrong way to reduce greenhouse gas emissions." Placing greenhouse gasses under the Clean Air Act is clearly the wrong way. Doing so would not only greatly harm the U.S. economy but also would fail to provide an effective response to the problem of climate change.

John Hart is director of news services for the American Farm Bureau Federation.