ANCHORAGE, Alaska - Nearly a dozen conservation groups are appealing to Agriculture Secretary Tom Vilsack to put a stop to two timber sales in the Tongass National Forest.

The groups say both sales would cut old-growth trees in roadless areas of the Tongass - the largest national forest in the United States.

The groups - including conservation heavy-hitters such as the Sierra Club, the National Audubon Society, Defenders of Wildlife and the Wilderness Society - are asking Vilsack to uphold President Barack Obama's commitment to protect undeveloped areas in the national forests.

They are making the appeal this week and next in an ad running in two publications seen primarily inside the Washington, D.C., beltway: CongressDaily and Politico.

The ad says in bold, white letters, "Secretary Vilsack, now it's up to you to protect our Tongass rainforest."

In a break with the previous Bush administration, Obama promised during the presidential campaign to support a 2001 Clinton administration rule to protect roadless areas in national forests from commercial logging.

Then, last May Vilsack said he would personally review proposals to log in roadless areas.

The conservation groups are objecting to a timber sale planned for Kupreanof Island. The Central Kupreanof timber harvest would require 15 miles of new roads at a $6 million cost to taxpayers. The other timber sale on Suemez Island, the Sue timber sale, would require 2.2 miles of new roads.

Both sales include inventoried roadless areas that are covered under the 2001 roadless rule, Jane Danowitz, director of the Pew Environment Group's U.S. public lands program, said Thursday.

Alaska Forest Service officials by advancing the sales are out-of-step with the stated intentions of the new administration, Danowitz said.

"It is now up to Secretary Vilsack to honor that commitment by stopping new roadless area logging in the Tongass and giving this crown jewel the full protection it deserves," she said.

Vilsack's May directive gave him sole decision-making authority over all proposed forest management or road construction projects in designated roadless areas in all states except Idaho. The Tongass was exempted from roadless protection in 2003.

Forest Service spokesman Ray Massey said the 2008 Tongass forest plan says that the agency will use low-value inventory in roadless areas to meet timber demands.

"It says it right in the plan. This should not be a surprise to anybody that we are doing this," he said. "You have to get it somewhere."

In July, Vilsack approved a timber sale in a roadless area of the Tongass. The sale allows Pacific Log and Lumber to clear-cut about 380 acres. About nine miles of roads will be constructed.