"Lowing" is a much nicer word.

We sing about it at Christmas. The cattle are lowing, the poor baby wakes.

It's a much nicer word, that is, than those that describe other sounds cows make. Mom would never yell at the kids for "lowing" at the dinner table. But if they emitted carbon dioxide or methane in the cow-like ways English speakers tend to describe more crudely, they might get sent to their rooms, or maybe even to the pasture.

The ... uh ... air cattle like to let loose has been causing a lot of anxiety among cattle ranchers and dairy farmers lately, both here in Utah and in the rest of the nation.

The EPA might even call it the rumor that refuses to die, that rumor being that the federal government will begin to tax cattlemen for all the stuff their herds put into the air.

Last month, the EPA issued a declaration that six gases are adding to global warming and are, therefore, major health hazards to Americans. Among the six are carbon dioxide and methane, two things cows deliver in spades. The EPA estimates that cows emit 20 percent of the methane generated in the United States, or roughly 5.5 metric tons per year.

That led to speculation that the government would begin levying a tax that would equal about $175 per dairy cow, according to calculations from the New York Farm Bureau. In Utah, officials have speculated this could cost dairy, beef and hog producers a combined $100 million, according to a report in this newspaper. That would mean either higher prices for food or much tighter profit margins in an industry where margins already are tight.

It's also not true, the EPA said. "There is no cow tax, period," an EPA spokeswoman was quoted as saying in this newspaper.

Well, then. But perhaps you can understand people being worried. The Obama administration has made a point of being a contrast to the Bush administration, which was seen as willing to cover up science in the name of politics. But this administration's decision to get tough on global warming is exposing some inconsistencies of its own. The EPA's report seemed aimed at urging new requirements against auto and truck manufacturers. But without a more clear direction, that would be confusing.

Even if automakers concentrate on building more affordable hybrid vehicles, where is the electricity coming from to fuel them? Strict regulations on coal-fired power-generating plants would make it more difficult to produce the power needed for those cars. Alternative generators using wind and solar power can make up only a small part of the difference, at least with the technology currently available. That leaves nuclear power, which faces mountains of hurdles, political and otherwise.