A spider web in a forest along Rock Creek in the Elkhorn Mountains west of Haines.

The U.S. Forest Service is proposing to cancel a rule that has banned the cutting of large live trees on national forests east of the Cascades in Oregon for the past quarter century.

The 21-inch rule, which the agency adopted in 1995, severely restricts logging of trees with a diameter greater than 21 inches measured four and a half feet above the ground.

Loggers can cut live trees larger than that generally only for safety purposes — around places where logs are loaded onto trucks, for instance, or near campgrounds or roads.

But Forest Service officials say the restriction has stymied their efforts to thin forests and thus reduce the risk of big, fast-moving wildfires.

“Adjusting the 21-inch limitation to reflect learning over the past 25 years would help streamline restoration of forests in eastern Oregon and make it easier to create landscapes that withstand and recover more quickly from wildfire, drought and other disturbances,” said Shane Jeffries, supervisor of the Ochoco National Forest in central Oregon and the agency official tasked with deciding whether to do away with the 21-inch limit on six national forests.

Those forests, in addition to the Wallowa-Whitman and the Ochoco, are the Umatilla, Deschutes, Fremont-Winema and Malheur.

The rule change would affect almost 10 million acres of public land.

On Aug. 11 the Forest Service published an environmental assessment of its proposal, starting a 30-day public comment period.

The 21-inch rule could be replaced with new regulations next spring.

The Forest Service imposed the 21-inch limit in 1995 after the Natural Resources Defense Council sought a court order blocking the Forest Service from cutting older trees, not specifically setting a 21-inch limit, east of the Cascades in Oregon and Washington.

The 21-inch threshold resulted from negotiations between the Forest Service and the Natural Resources Defense Council.

According to the Forest Service, a team of agency employees recommended the 21-inch limit as a temporary measure, to be replaced with more detailed policies within 12 to 18 months.

Those policies would be designed to preserve old trees and manage forests to increase the number of such trees in the future, according to the Forest Service.

But despite that goal, the 21-inch limit remains in effect.

The Forest Service is proposing to replace that strict rule with a more flexible strategy that would aim to protect trees that are at least 150 years old, as well as grand fir, white fir and Douglas-fir trees more than 30 inches in diameter, and trees of other species, including ponderosa pines and tamaracks, larger than 21 inches.

Over the past 25 years the agency has on occasion tried to amend the 21-inch limit.

And in one notable case the agency tried to exempt a specific logging project from the rule. That was the Snow Basin project on the Wallowa-Whitman National Forest in eastern Baker County.

Wallowa-Whitman officials contended that to achieve their goal of protecting from wildfire forests that had historically been dominated by ponderosa pines and tamaracks but in recent decades largely replaced by Douglas-fir and grand fir trees, it was necessary to remove many of the firs, some of which were larger than 21 inches in diameter.

Snow Basin included four timber sales. In 2014 Boise Cascade logged most of the first sale and did a small amount of cutting on the second when a federal court, ruling on a lawsuit filed by environmental groups, halted the project.

A federal judge ruled that the Wallowa-Whitman couldn’t ignore the 21-inch limit for a single project, Snow Basin, because the issue affected the entire Wallowa-Whitman.

Veronica Warnock, the conservation director for Greater Hells Canyon Council in La Grande, said the organization has always encouraged the Forest Service to address the issue of preserving large trees at a “landscape” level rather than for specific projects such as Snow Basin.

Warnock disputes the Forest Service’s claim that cutting trees larger than 21 inches in diameter is necessary.

Indeed, Warnock contends that the purpose of the ban on logging such trees is as relevant today as it was 25 years ago.

She said those trees store the majority of the carbon sequestered in forests.

Yet Warnock said the Forest Service didn’t even address the issue of carbon storage, and its influence on climate change, in the environmental assessment that looks at the possible effects of ending the 21-inch limit.

Many areas of national forests lack large dead trees — snags — that serve as habitat for birds and other wildlife, Warnock said.

A significant percentage of the old trees in national forests east of the Cascades were logged between World War II and the late 1980s, which is one reason environmental groups lobbied, and in some cases sued, to prevent logging of the remaining older trees.

Warnock agrees with the Forest Service that the 21-inch limit was intended to be a temporary rule when the agency enacted it in 1995.

But she contends the Forest Service has not replaced the rule with a policy that would adequately protect large trees. And the agency’s current proposal would not accomplish that goal, either, she believes.

Instead, Warnock said, the Forest Service is in effect proposing to give national forest supervisors the authority to cut large trees with no limit on the number or size.

She said she believes that ending the rule would lead to widespread logging of trees larger than 21 inches, especially in areas that haven’t been logged recently.

“There’s a lot of room to improve the (21-inch) rule, but we believe going forward we still need enforceable protection (for large trees) rather than giving full discretion to forest supervisors,” Warnock said.

Although Forest Service officials say the 21-inch limit has made it more difficult to thin crowded forests and reduce the wildfire danger, Warnock notes that in many such projects most of the trees removed are smaller than 21 inches.

Arvid Andersen of Baker City has a much different view of the 21-inch limit.

Andersen is a private forestry consultant.

He describes the 21-inch limit as “arbitrary” and he believes it has contributed to the severity of some wildfires by restricting the Forest Service’s ability to thin forests and reduce the fuel load.

Andersen said he was the contractor on a thinning project on the Wallowa-Whitman several years ago and because loggers couldn’t cut trees larger than 21 inches, taxpayers had to subsidize the removal of the smaller, less valuable trees.

He’s especially worried about how the 21-inch limit could affect the proposal to cut trees in Baker City’s 10,000-acre watershed, which is managed by the Wallowa-Whitman. Andersen is a Baker City Council member and a longtime advocate of logging in the watershed to reduce the risk of a fire that could foul with ash and mud the streams and springs the city taps for its water supply.

A large fire in the watershed could force the city to find a temporary alternative source of water as well as build a filtration plant that could cost several million dollars.

“You can cut all the little trees you want but you’ve got to get that fuel loading down,” Andersen said.

He said he doesn’t advocate for wholesale removal of large trees, but he believes the Forest Service should have more flexibility than it has now with the 21-inch limit.

Warnock also criticizes the Forest Service for studying the potential effects of eliminating the 21-inch limit through an environmental assessment rather than the more in-depth environmental impact statement.

The 1969 National Environmental Policy Act, which requires federal agencies to study the potential effects of their actions, states that an environmental impact statement should be done for projects likely to have a significant effect.

Warnock contends that doing away with the 21-inch limit on six national forests clearly meets that criteria.

“There’s no way there’s not going to be significant effects,” she said.

Greater Hells Canyon Council joined four other organizations — Oregon Wild, Western Environmental Law Center, Sierra Club and Central Oregon Landwatch — in writing a letter on Aug. 12 to Forest Service Regional Forester Glenn Casamassa asking him to require an environmental impact statement for the proposal and extend the public comment period to at least 90 days.

Oregon’s U.S. senators, Ron Wyden and Jeff Merkley, both Democrats, have also urged the Forest Service to give the public more time to comment.

Webinars scheduled

A 30-day public comment period is underway for the U.S. Forest Service’s environmental assessment and proposed amendment to the 21-inch harvest standard.

The agency will hold a pair of webinars, scheduled for 6-7:30 p.m. Aug. 19 and 1:30-3 p.m. Aug. 20, to provide information and gather feedback. Registration information will be posted on the project’s website at https://go.usa.gov/xvV4X. Groups and individuals can also submit written comments via email to SM.FS.EScreens21@usda.gov.