WENATCHEE — An alpine species of pine that is stressed by mountain pine beetles and a disease called rust may warrant protection under the Endangered Species Act, the U.S. Fish and Wildlife Service announced.

Whitebark pine, which in North Central Washington grows only on mountains above approximately 6,000 feet, is undergoing a status review by the agency.

The nonprofit Natural Resources Defense Council — which petitioned to list whitebark pine as threatened or endangered — says climate change is also threatening survival of the tree.

The trees are fairly widespread at high elevations across the Okanogan-Wenatchee National Forest, and are showing signs of stress, according to U.S. Forest Service officials.

“Anybody who spends any time in the high country knows the whitebark pine. It’s hard not to love it,” said Connie Mehmel, forest entomologist.

As for listing the tree as threatened or endangered, Mehmel said, “I myself wouldn’t try to make a call on whether that’s appropriate. But it certainly has some threats. It’s a species with a pretty narrow range, and it has things happening that make you wonder if it’s going to continue to occupy that range,” she said.

The hearty five-needle pine is found on cold, windy mountainsides, where other conifers would struggle to survive. They often grow in clumps or clusters, and are an important component of the alpine ecology, regulating runoff by slowing snowmelt, and reducing soil erosion by growing soon after wildfires or other disturbances.

Their seeds are also a high-energy food source for birds and mammals, and because their seeds have no “wings” to carry them to new places, the trees depend on animals for dispersal.

Among them is the Clark’s nutcracker, a loud, jay-like gray-and-black bird who feeds on seeds in the whitebark cones, then buries the rest in a hide-away to eat later.

The bird may return, but they often don’t eat all of the seeds they left in their cache, thereby planting a new grove of whitebark pines.

Mehmel said it’s worth exploring whether the trees should be protected.

“Anything that makes its living at those high elevations is always kind of at the edge of a narrow niche. There are not many places it can grow,” she said, “So if things start to threaten it, we become alarmed.”

Whitebark pines in the Okanogan-Wenatchee National Forest are inflicted with the white pine blister rust, a non-native disease that is also found in the lower elevation Western white pines, she said.

She said the whitebark pines are normally resistant to mountain pine beetle, because the little bugs have a hard time completing their life cycle during the short summers where whitebarks grow.

But things could be different with climate change, and a longer spring and summer season in higher elevations.

“It gets more and more likely that they’ll be able to complete their life cycle, and more likely to successfully attack the trees,” particularly if they’re already stressed by disease, she said.

Whitebark pines are found in the Western United States and Canada, in mountains from British Columbia to central California, and in the Rocky Mountain ranges from northern British Columbia and Alberta to Nevada.

The U.S. Fish and Wildlife Service is requesting scientific information about whitebark pines until Sept. 20.

Mehmel said the trees have never been commercially harvested, so a listing would have no impact on logging.

Listing it would likely mean more emphasis on finding ways to protect the tree from rust and mountain pine beetle, she said. The agency might also focus more on gathering seeds and distributing them to disturbed areas in higher elevations, she said.

K.C. Mehaffey: 997-2512

mehaffey@wenatcheeworld.com