Forest Service seeks to save aspen groves

The agency’s prescription, however, calls for the controversial cutting of mature firs and pines.

Forest Service officials in Baker County want to kill several hundred fir and pine trees to save several thousand aspens.

What they haven’t decided is whether to sell the firs and pines to a mill, or to leave them, dead but standing.

In the meantime, officials from the Whitman Unit of the Wallowa-Whitman National Forest want to know which option, if either, the public prefers.

Whitman Ranger Ken Anderson recently released a draft environmental assessment for the Tremble Aspen project on the Pine District north of Halfway.

He’ll accept comments through the end of May.

The Forest Service unveiled the Tremble Aspen project about three years ago.

(Tremble, in this case, refers to the aspen’s Latin name, “populus tremuloides.” That moniker came about because aspen leaves, due to their square stems, move, or tremble, in the slightest breeze. They’re known as “quaking” aspen for the same reason.)

Officials worry that mature conifer trees — mainly grand firs and Douglas-firs, but also some ponderosa pines and tamaracks — are casting shade over dozens of groves of sun-loving aspens on the Pine District, said Joe Sciarrino, who works for the district.

Left in shadow, the roots of adult aspens are less likely to produce baby trees — genetically identical clones called “suckers” — which are vital to perpetuating aspen groves.

The tall conifers also take water and soil nutrients, further weakening the aspens. However, Sciarrino said the research he’s read shows that shade suppresses aspens more than does the competition with conifers for water.

The end result of this “conifer encroachment” is the gradual decline of aspen.

The Forest Service’s solution, which it has employed for about a decade on the Pine District, is to cut some of the conifers to let the sun shine on the aspens.

That tactic has rejuvenated many aspen groves on the district, Sciarrino said.

After conifers are cut, the nearby aspens often send up thousands of suckers, he said.

The Tremble Aspen project is different, though, from its predecessors in one significant, and potentially controversial, way.

So far the Pine District has allowed only conifers smaller than 21 inches in diameter to be felled for aspen preservation.

That’s because Forest Service officials agreed, in 1994, to stop cutting live trees larger than 21 inches in Eastern Oregon national forests so as to protect old growth stands.

However, Sciarrino said that at many aspen groves on the Pine District, the conifers that threaten the aspens are bigger than 21 inches.

The Tremble Aspen project includes 28 of those groves, totaling 104 acres.

The Pine District’s preference is to cut the encroaching conifers and sell the logs to mills.

Cutting live trees larger than 21 inches requires the Wallowa-Whitman to amend its 1990 Forest Plan.

Officials estimate they would fell 663 trees larger than 21 inches — 68 percent of the trees being grand firs, 19 percent Douglas-fir, 10 percent ponderosa pine and 3 percent other species.

The timber sale would produce an estimated 692,000 board-feet of timber.

That’s a relatively small sale for the Wallowa-Whitman, where most sales have between 1 and 3 million board-feet.

Sciarrino said all the 21-inch-plus ponderosa pines targeted for cutting are so-called “black bark” trees — pines that don’t have the orange bark characteristic of old growth ponderosas.

He said the Forest Service does not intend to cut any ponderosas that are larger than 21 inches and have orange bark.

Nor would loggers be allowed to harvest Douglas-firs larger than 32 inches in diameter, according to the environmental assessment.

When the Forest Service announced the Tremble Aspen project in 2006, representatives from two environmental groups, Oregon Wild and the Hells Canyon Preservation Council, said that although they endorsed the Forest Service’s goal of protecting aspen, they disagreed with the agency that cutting 21-inch-plus conifers was necessary to preserve the groves.

They suggested that instead the Forest Service kill the conifers by slicing them with saws — a process known as girdling — but leave the trees standing to serve as habitat for birds.

The dead trees would not block the sun after their needles fall, nor would the trees compete with aspens for water and nutrients.

Prompted by the environmental groups’ comments, the Forest Service added to the draft environmental assessment the option of killing, but not removing and selling, the encroaching conifers.

Tim Lillebo, who works for Oregon Wild, said he’s pleased the Forest Service added a girdling-only alternative.

“Congratulations to the Forest Service for looking at all options,” Lillebo said.

Girdling trees not only creates snags that are habitat for birds and other species, but it avoids some of the potentially harmful effects of logging, including compacting the soil with heavy equipment.

Sciarrino said girdling the conifers would have most of the same benefits as felling them.

He pointed out, though, that girdled trees will retain their needles — and thus keep casting shade over the aspens — for about one year after girdling.

Also, the Forest Service would have to pay someone to girdle the conifers, whereas a timber sale would pay for itself.

At least it would if a mill was willing to buy the logs, he said.

Sciarrino said that due to the volatile lumber market there’s no guarantee that any timber sale — even one such as Tremble Aspen that includes big trees — would attract a buyer.

Lillebo thinks the Forest Service could potentially employ both tactics — logging and girdling — because either can be appropriate depending on the situation at a particular aspen grove.

Sciarrino said Anderson expects to choose either the logging or girdling option later this summer.

If it’s the former, the timber sale would be offered before Oct. 1, Sciarrino said. Logging probably wouldn’t happen until 2010.