CANDLESTICK PARK, San Francisco -- The answer to the most common question Yokohama Tire gets about a new line of car tires made with orange oil is "no."

The tires do not give off a citrus-y smell.

But the tires do have a lot of other benefits, which Fred Copeland, Yokohama's director of marketing, likes to point out. For one thing, the new tires are some of the greenest rubber on the road. 80 percent of the tire consists of materials that do not derive from petroleum.

Individual tires contain about 10 gallons of oil, according to rubber recycler Lehigh Technologies, and about 300 million get tossed out every year in the U.S. As a result, the tire industry consumes 3 billion plus gallons of oil a year to just replace old tires. The U.S. in total consumes about 310 billion gallons of oil a year. Thus, tires contribute a small, but noticeable, amount of oil. Oregon State researchers are similarly working on a cellulosic tire.

Second, the tires provide better traction and 20 percent less rolling resistance than standard petroleum tires. The tires also contain an interior lining that reduces air leakage. The combination of lower rolling resistance and less leakage leads, ideally, to better gas mileage.

In part, the improvements are due to the inherent qualities of orange oil. "It heats up quickly for better traction," he said.

Thus, when drivers accelerate, the oil heats up, the tire rubber softens, and grip improves. When you hit a level speed, the tire cools off a bit and rolling resistance drops. But if you have to make a sudden lurch to make an exit, the tires heat up and improved gripping occurs.

Yokohama began experimenting with orange oil to improve grip in racing tires. It has been tinkering with the formula and this year brought some to the U.S. for races. The commercial versions coming out now are suited mostly for hybrids and compact cars. They cost about 15 percent to 20 percent more than a conventional tire, or close to the same cost of a high-end tire.

Yokohama gets the peels from an orchard in Japan. Unlike corn ethanol, the food versus fuel trade-off isn't severe. The oranges get used for juice. Although you could ostensibly squeeze the peels for food flavoring or to use them to decorate Christmas cookies, orange oil is largely a byproduct off a byproduct.

How do they drive? Quite well actually, or at least as well as an ordinary driver can tell. In the acceleration-and-swerve test and the slalom course, the car didn't slide around. It felt like a car with new tires. Going through the turns too fast made them squeal, but they weren't obnoxiously loud.

If you don't see a lot of accident reports or recalls, you can likely expect to see more organic tires.

The racing and touring versions of Yokohama's tires.

The tires are primarily made out of orange oil, silica, natural rubber and organically produced (i.e., non-fossil fuel) carbon. Eighty percent of the content is non-fossil fuel material.

The orange Mini Cooper, in case you missed the point.