PENDLETON — A group of scientists and university professors is disputing claims made by environmental activists in a lawsuit over logging certain trees on six national forests in eastern Oregon and southeastern Washington.

The issue centers on a series of land-management standards known as the Eastside Screens, adopted in 1995 to protect wildlife habitat and water quality on approximately 10 million acres in the Umatilla, Wallowa-Whitman, Malheur, Ochoco, Deschutes and Fremont-Winema national forests.

One of the rules included a ban on harvesting any trees larger than 21 inches in diameter at breast height.

The U.S. Forest Service axed the 21-inch rule in January 2021 — five days before President Donald Trump exited the White House.

In its place, officials adopted a more flexible guideline that generally calls for protecting old and large trees, though it allows for exceptions to achieve long-term forest-restoration goals, such as hazardous fuels reduction to improve wildfire resiliency.

Under the guideline, “old” trees are defined as at least 150 years, and “large” trees are defined as defined as 30 inches in diameter at breast height for grand fir and white fir, and 21 inches for other species.

Six environmental groups are suing the Forest Service in the U.S. District Court in Pendleton, alleging the agency’s decision was rushed and lacked a full environmental analysis, violating several federal laws including the National Environmental Policy Act, Endangered Species Act and National Forest Management Act.

Plaintiffs include the Greater Hells Canyon Council, Oregon Wild, Central Oregon LandWatch, Sierra Club, WildEarth Guardians and Great Old Broads for Wilderness.

The Eastern Oregon Counties Association and American Forest Resource Council, a timber industry group, are intervening in the case on behalf of the Forest Service, seeking to uphold the Eastside Screens amendment.

Environmental groups contend that removing the 21-inch rule is “highly controversial” and will have “uncertain effects” on the landscape.

But in a letter signed by 15 forest ecologists, they argue there is no meaningful scientific controversy.

James Johnston, an assistant professor in the College of Forestry at Oregon State University, made a motion to file an amicus brief with the court on Feb. 10, which includes the letter. It outlines historical conditions in the forests, and how those conditions have changed over decades of wildfire, fire suppression, logging and other disturbances.

According to the letter, in the 25-plus years since the Eastside Screens were adopted, the number of trees larger than 21 inches in diameter has increased 17%. Younger, shade-tolerant species are crowding out older, more fire-resistant species, leaving the overstocked forests more susceptible to drought, fire and insects.

“The overwhelming majority of research and observations show conclusively that east side Oregon and Washington forests have undergone dramatic ecological changes and that these changes have left valuable resources vulnerable to uncharacteristic disturbances,” the letter states.

The Forest Service’s order to replace the 21-inch rule with a more flexible guideline “made reasonable conclusions from the scientific literature about the historical condition of east side forests, changes to these forests over time and the need for restoration,” the scientists wrote.

In their motion for summary judgment, the plaintiffs cite a 2020 report by Dominick DellaSala, chief scientist at the nonprofit conservation group Wild Heritage, and William Baker, emeritus professor at the University of Wyoming.

That report states the recovery of large trees in the east side forests is “far from complete” after decades of logging dating back to the 1920s.

Preserving large trees is critical, the report continues, because they provide invaluable habitat for birds and wildlife, shade in riparian areas to keep water cool for fish, act as a carbon sink and help to stabilize soil.

In their letter, scientists state the DellaSala-Baker study is “full of mischaracterizations of other scientists’ research and contains no meaningful theoretical or empirical rebuttal of our findings or our colleagues’ findings.”

“Although a handful of independent researchers make a number of claims that give the appearance of controversy, there is no meaningful controversy among the scientific community with respect to changes to forests over time or the effects of common restoration actions,” they wrote.

Plaintiffs in the case have opposed Johnston’s motion to file an amicus brief, arguing it is duplicative of the Forest Service’s position and would introduce impermissible extra-record evidence.

Fifteen scientists have signed on to a letter disputing whether there is “meaningful scientific controversy” over removing the Forest Service’s 21-inch harvest rule on six national forests in eastern Oregon and southeast Washington. 

They include:

• James Johnston, assistant professor, Oregon State University College of Forestry.

• Derek Churchill, forest health scientist, Washington State Department of Natural Resources.

• Don Falk, professor, University of Arizona School of Natural Resources and the Environment.

• Jerry Franklin, professor emeritus, University of Washington College of Forest Resources.

• Keala Hagmann, research ecologist, Applegate Forestry LLC.

• Lori D. Daniels, professor, University of British Columbia Department of Forest and Conservation Sciences.

• Matthew Hurteau, professor, University of New Mexico Department of Biology.

• Meg Krawchuk, associate professor, Oregon State University College of Forestry.

• Norm Johnson, emeritus professor, Oregon State University College of Forestry.

• Peter M. Brown, director, Rocky Mountain Tree-Ring Research.

• Robert W. Gray, fire ecologist, R.W. Gray Consulting.

• Scott Stephens, professor of fire science, University of California-Berkeley.

• Susan Prichard, fire ecologist, University of Washington School of Environmental and Forest Sciences.

• Thomas Deluca, dean, Oregon State University College of Forestry.

• Trent Seager, director of science, Sustainable Northwest.