Forest officials race birds to help ailing pines

In the midst of a persistent bad spell for whitebark pine populations in Northeastern Oregon, 2011 stands out as a pretty good year.

Whitebarks, which grow at higher elevations than other conifers in the Elkhorn and Wallowa mountains, are suffering from a two-pronged attack: white pine blister rust, and mountain pine beetles.

That combination has killed a significant number of whitebarks in the region over the past 20 years or so, said Sabine Mellmann-Brown, who is the Forest Service’s ecologist for the three Blue Mountains national forests: Wallowa-Whitman, Malheur and Umatilla.

This summer she and other researchers examined about 100 test plots in the Elkhorns near Anthony Lakes, the Wallowas on Mount Howard and near Echo Lake in the West Eagle Creek headwaters, and in Idaho’s Seven Devils.

The plots in the Elkhorns and Wallowas had last been surveyed in 2005.

“Conditions, especially in the Elkhorns, seem quite deteriorated,” Mellmann-Brown said on Thursday. “In some areas the infestation rate is up to 90 percent (of whitebarks).”

Although blister rust can take up to a decade to kill a tree, the disease also weakens pines and makes them much more susceptible to beetles, she said.

And beetles, unlike blister rust, act fast — the insects can kill a tree in a month.

The prognosis, Mellmann-Brown concedes, is “bleak.”

But not completely.

The good news for 2011 is that the surviving whitebarks produced an unusually prolific crop of seed cones — enough cones, in fact, to entice officials from the Wallowa-Whitman National Forest to grab some.

They just had to beat the birds to the prize. More about that later.

The Wallowa-Whitman’s goals in harvesting the cones were twofold.

First, the forest’s haul of several thousand seeds will be preserved, and in some cases germinated, to ensure there is a source of new trees to replace whitebarks lost to disease or insects, said Robyn Darbyshire, the Wallowa-Whitman’s chief silviculturist (tree expert).

“Overall it was a good cone year,” Darbyshire said. “We were quite happy with what we collected.”

Second, geneticists will study the seeds and try to figure out which whitebarks are naturally resistant to blister rust or beetles — or, ideally, to both.

“Obviously we only want to replant seeds from trees that have a resistance,” Mellmann-Brown said.

The Wallowa-Whitman hired a contractor to climb 14 whitebarks in the Elkhorns near Anthony Lake and pluck cones from them.

Actually the workers had to ascend those trees twice.

Because of the aforementioned birds.

Specifically, the Clark’s nutcracker, a gray-and-white, jay-like bird that has, well, a certain affinity for whitebark pine seeds.

Clark’s nutcrackers gather whitebark seeds every summer and store them in caches for their winter food supply.

This is helpful to the pines as well, because the birds disperse the seeds — something whitebarks, unlike some other conifers, don’t do on their own.

Because Clark’s nutrackers don’t eat every seed they seize (sometimes they misplace a cache, Darbyshire said), the birds are effective avian reforesters, only they work with seeds rather than seedlings.

The challenge for human cone collectors, then, is to get ahead of the birds.

“It’s a race,” Darbyshire said.

And so in August the Wallowa-Whitman’s hired tree climbers first fitted beak-proof wire cages around cones on the 14 whitebarks.

Then, in early October, they returned to gather the seed-filled cones.

The cones were taken to a Forest Service facility in Bend where the seeds will be extracted, dried, cleaned and stored.

Some of those seeds will be germinated in a Forest Service nursery that will raise the seedlings for replanting.

Forest Service officials are considering other options as well, Darbyshire said, including planting seeds rather than seedlings.

Regardless of the method, the objective will be the same: to replace dead whitebarks with new trees that are better able to resist both blister rust and beetles.

This is vital because the Forest Service has no effective way to protect trees from either threat, Mellmann-Brown said.

Blister rust is especially virulent.

Once a whitebark pine is infected with blister rust, it’s basically “a matter of time” before the tree dies, she said — although, as she noted, the process can take many years.

With beetles, the situation is only slightly more promising.

It is possible to nail to a tree a card that contains basically an “anti-pheromone” — a substant that, in effect, makes the tree less attractive to beetles, Mellmann-Brown said.

The current outbreak of blister rust and beetles, which started around the late 1990s, isn’t the first in the Blue Mountains.

In the 1970s the same combination ravaged first the lower-elevation lodgepole pine stands before migrating up into the alpine zones where the whitebarks live.

But the current infestation is perhaps the most severe that scientists have studied, Mellmann-Brown said.

Nor is it confined to Northeastern Oregon.

“It’s affecting whitebarks all over the Rocky Mountains,” she said.

Researchers in Glacier National Park, for instance, aren’t sure the species will even survive there.

In the Yellowstone region, officials say beetles killed 700,000 whitebarks in 2004 alone.

The whitebark’s plight prompted the U.S. Fish and Wildlife Service to consider designating the pine as a threatened or endangered species.

The agency decided in July that although such protection is warranted, other species are a higher priority.

Although blister rust and beetles are the most obvious threats to whitebark pines, there are others, Mellmann-Brown said.

The Forest Service’s success at fighting wildfires, for instance, has allowed other species, primarily subalpine fir, to encroach on whitebark forests and weaken the pines.

Researchers also believe that climate change has added to the whitebark’s woes because the winters are no longer harsh enough to curtail the spread of beetles.

Mellmann-Brown said she hopes to also collect cones from limber pines, a related species that grows in the Wallowas but not the Elkhorns.