Having created zero-waste factories, recycled plastic upholstery and low-emission hybrid engines, automakers are opening a new front in the drive to appear eco-friendly — “sustainable” wood interior trim.

Instead of searching the world for exotic woods, long a mark of elegance in premium brands, some are turning to suppliers who dredge rivers for old logs and use fast-growing woods such as bamboo or eucalyptus to create the wood trim pieces that surround drivers and passengers in luxury cars.

The move avoids criticism for automakers that while their new fuel-saving engines are cutting carbon emissions, their choices of interior trim could destroy endangered old-growth forests. The trend is especially seen in cars billed as eco-friendly, such as hybrids or electrics.

Sure, the total amount of veneer in a typical luxury car is less than on an old dining-room chair, so the effort is mostly symbolic. But it’s good business: Sustainable wood trim adds another little feature to make buyers feel good about their purchase.

“Every little bit counts in terms of manufacturers trying to raise awareness,” says Roland Hwang, transportation program director for the Natural Resources Defense Council, which is active both on clean-car and forest-protection issues. “It shows there is a growing market for sustainable products.”

What some automakers are doing to splinter off from the competition:

•Bamboo. To underscore the sustainability aspect of its new Lexus hybrid sedans, Toyota chose fast-growing bamboo for trim. It’s one of the wood choices in the midsize ES 300h and flagship LS 600h L, and is the only wood trim for the sporty GS 450h. “It’s a light, almost bleached wood,” says spokesman Bill Kwong. It can be found on both the steering wheel and dashboard.

•Eucalyptus. BMW’s i3 plug-in electric car will have a swoopy wood panel across the top of the dashboard made of eucalyptus. It’s being culled from “certified sustainably managed European forests and treated using natural materials,” BMW says.

•Reclaimed logs. Fisker, the troubled maker of stylish hybrids, could claim that no tree was injured in building its cars. Even though production of its Karma sedan is suspended now, it prided itself on using only reclaimed timber for its interiors: white oak from the bottom of Lake Michigan, “rescued wood” from trees killed by California wildfires and trees that have fallen naturally.

•Old fence posts. For its posh Ram Laramie Longhorn pickup, Chrysler Group designers chose European walnut from trees being used as fence posts and imprinted with markings from the barbed wire wrapped around them, in keeping with the truck’s gentleman cowboy theme.

A trim material once plentiful in luxury cars and now banished is wood-look plastic. While it can be made to look virtually the same as highly polished hardwoods and holds up better to punishment from sunlight, it isn’t the kind of authentic material that luxury-car buyers are demanding.

Instead, automakers are trying to find better ways of using the real thing and increasingly are using an open-grain look that can’t be mistaken for plastic.

In the Ram, the goal was to make the wood trim feel like the worn stock of a beloved shotgun or rifle, “the whole ranch atmosphere,” says Ryan Nagode, chief interior designer for Ram and Fiat. “It really hopes to show it’s real wood.”