The timber industry is scoffing at a campaign by environmentalists and the American Cancer Society to protect a tree with bark that produces a rare and potent cancer-fighting drug.

The yew tree, which thrives in the shade of the Pacific Northwest's virgin forests, is fueling tensions between loggers and environmentalists, already at odds over the northern spotted owl.Ten environmental groups and medical researchers Wednesday sent a petition to Interior Secretary Manuel Lujan Jr. asking that the Pacific yew tree be listed as a threatened species under the Endangered Species Act.

They said the tree should be protected because of its role in the fight against cancer and because it represents another diminishing piece of the Pacific Northwest's virgin forests.

The timber industry accused environmentalists of shamelessly exploiting cancer patients in an effort to stop logging.

The Pacific yew's bark is the source of a drug called taxol, which has proven effective in treating ovarian and other cancers.

The tree grows primarily in the shade of mature forests from northern California to Alaska. Environmentalists say logging threatens the yew and therefore the future supply of taxol.

The petition was filed amid continued debate over the fate of virgin forests in the Pacific Northwest. The U.S. Interior Department recently listed the northern spotted owl as a threatened species, bringing timber industry predictions that thousands of jobs will be lost as logging is stopped to protect the birds.

Bruce Manheim, an attorney and scientist with the Environmental Defense Fund, said the request that the yew tree be protected expanded the controversy.

"The debate over the future of the ancient forests involves more than a choice between spotted owls and logging jobs - our ability to assure an adequate supply of this novel anti-cancer compound (taxol) is at stake as well," he said.