Two things upfront: Napa was once a cow town, and Gary Larson should be illustrating this column today. A reader kindly passed along news of a business innovation outstanding in its field. Literally.

The field itself is an odorous one, full of guilty cows whose positive contributions to the American meat-and-dairy diet may not outweigh their unwanted contributions to global warming. Really.

Bovines who have never driven an SUV or wasted a single kilowatt-hour in their lives pass enough methane into the air to make them targets for a.) anti-cow prejudice and b.) greenhouse gas reduction initiatives. It’s not their fault entirely, but cattle burp and the planet warms.

So a national food distributor, Stonyfield Farms, is boasting about a burp-reduction program for dairy cows in the land of Ben & Jerry’s — that would be Vermont — which, of course, has an outpost in downtown Napa.

Over your next bowl of Cherry Garcia, ponder the fact that if your ice cream came from a cow on a methane reduction diet — say alfalfa, flax or hemp — you might be on a lower fat diet yourself. According to Stonyfield Farms, the diet not only reduced emission up to 18 percent, but as a happy accident also reduced saturated fats in the milk. (Don’t rush out for ice cream yet, as the Vermont cows in the study are busy making organic yogurt at the moment.)

The big claim by this distributor shouts from their press release, “If every U.S. dairy were to adopt this approach, in less than one year, the amount of greenhouse gas emissions we could reduce would be the equivalent of taking more than half a million cars off the road.”

That’s more dramatic than winegrapes taking more than half a million cows off the valley floor. Napa cattle rancher Judy Ahmann, whose Ahmann Ranch runs cattle on sites including Carneros and the east side of Lake Berryessa, said, “Up until 1973, beef was the No. 1 agricultural product in Napa.” 

Dan McQueeney, whose cattle-ranching family goes back four generations here, recalls, “There used to be a 5,000 head feed lot on Atlas Peak Road. Right across from the country club, a former cattle ranch.”

Did the smell ever bother the golfers, I wonder? McQueeney also mentioned a slaughter house on Soscol Avenue, and named a half dozen dairies that supplied local milk products. Of the 10,300 head of commercial cattle in Napa last year, all were beef producers. Napa’s dairies are gone. Only the movement toward localizing food would bring back the milk cows.

If Napa revived a dairy or two, I trust they would use the methane reduction diet rather than the engineering being attempted in Canada.

Researchers at the University of Alberta want to re-engineer a cow that burps less. But Napa would do the sustainable thing — feed a better diet to existing livestock, and then raise a wineglass to the improved post-meal etiquette of cows.