Seeing the forest for the trees: restoring fire-devastated forest habitat

Updated: Jul 27

by Lyn Gubser, PhD

June 15, 2021

Prior to 2020 the Tillamook Burn was the largest forest fire episode in American history. While global warming is increasing the frequency and intensity of forest fires in the American West, wildfires in these woods are nothing new. How to recover and the pitfalls of recovery offer valuable lessons to be learned from Oregon’s wildfire experience, especially when it comes to the conservation of birds and other wildlife.

The Wilson's Warbler nests along streams in Oregon's forests.

Growing up in Oregon during the early 1940s, one of my most vivid memories is that of smoke-filled skies that left a blanket of soot covering everything on our Willamette Valley farm from cars and tractors to gardens and pasture. From 1933-51 a series of fires, which became collectively known as the “Tillamook Burn” because their epicenter was Tillamook County, destroyed more than 140,000 hectares of old-growth forest in the Coastal Mountain Range.

Some of the most destructive of these fires were intentionally set during the war years from Japanese submarines launching balloons that were positioned to ride the onshore winds and drop incendiary devices on Oregon forests. Their intent was to destroy the timber that was being employed in Portland shipyards frantically at work to rebuild America’s Pacific Fleet after its devastation at Pearl Harbor. As a boy I recall my parents joining civil units of firewatchers that drove to the mountains to man tall wooden watchtowers that had been hastily built so observers could watch for these incendiary balloons, usually released at night. Most fires, however, were the result of human carelessness, poor forest management practices, and unregulated logging operations that pirated forests for logs and quick profits, leaving behind piles of combustible debris. Natural lightning-caused fires in Oregon’s wet coastal forests are historically rare.

The Acorn Woodpecker is one of hundreds of bird species that nest in Oregon's forests.

The destructive effects of the Tillamook Burn on trees and water resources were readily apparent. Less immediately conspicuous was its impact on birds and other wildlife, which in an area of more than 1,295 square kilometers was close to total extermination.

Throughout the 1950s and early ‘60s the hellish and lifeless landscape of “The Burn” was one of grotesquely twisted and blackened trees, mountains of ash eroded by creeks of mud and rocks that cut gashes into hillsides eventually contributing to landslides and further devastation. Pools of black ooze stood where crystal-clear lakes had once teemed with life.

Dozens of logging communities had been wiped out by the fires. And Oregon’s once premier lumber industry was clamoring for immediate relief and supportive of anything that would restore their livelihoods. The political pressure the forest-products industry exerted on state and national governments was intense. Money was found to begin reforestation projects and to support research at Oregon State University and the US Forest Service to find fast-growing trees that could stop the erosion, clean up streams, and within as few as 25 years might be harvestable, if only for paper pulp.

As part of a Smokey Bear program, the U.S. Forest Service enlisted hundreds of civic and youth organizations to plant millions of seedling trees to speed the replacement of Oregon forests. While an elementary school student I sloshed through the cold rain and mud to do my share to bring back the forests and animals.

And these measures at first appeared to work. By the 1960s thousands of acres of lush green conifers waved in the coastal breeze to beach-bound tourists, loggers, and politicians who marveled at the dramatic change from black to green of the Oregon Coastal Mountains. But while these citizens as well as the folks logging and forest product industries may have been delighted with the success of millions of taxpayer dollars pumped into forest restoration, fisheries industry people, ecologists, and other naturalists were becoming increasingly aware of a major problem: when it came to fish, birds, and other wildlife, what they had redeveloped were not forests, but plantations with all the features of crop monocultures and devoid of most other life.

The non-native trees were also defenseless. Without birds to eat the insects that began to demolish plantings, broad swaths of infested trees began to die off, creating fire hazard and erosion nightmares. Fighting predators with insecticides was costly not only in dollars, but in the pollution of streams and lakes, reversing efforts to restore salmon and steelhead breeding waters. It became obvious that the success of long-term forest restoration is highly correlated to the careful management of forests as habitat. Never before did the old adage “can’t see the forest for the trees” ring more true. For it turns out that the trees are only a part of the forest. Forests don’t provide habitat, forests are habitat. Trees support a natural gestalt where the forest system is far greater than the sum of its parts.

The Great-horned Owl inhabits Oregon forests year-round.

There were foresters, fish and game biologists, botanists and other biologists who had warned that allowing the forests to regenerate was a complex task that would require decades to complete. However, impatient forest products corporations, loggers and logging communities, pressured government agencies to move as quickly as possible to restore logging operations to create jobs, generate corporate profits, and rebuild local economies. Thus corners were cut that ultimately were to slow the progress of forest recovery, taking longer to bring back healthy woodlands than had a more holistic approach to forest management been initially pursued.

In the latter 1960s the failure of earlier restoration efforts became apparent. This, coupled with the continuing commercial ravaging of Oregon’s forests, the alarming loss of species, and the growing concern over the nearly complete destruction of old-growth timber, led to a sea change in public attitudes toward forest management. Environmental groups, including the Sierra Club, Nature Conservancy, and others, joined with leading industry advocates concerned with their future health if industry practices didn’t change. The result of their efforts was the Oregon Forest Practices Act of 1971, the first of its kind in the United States.

The Pacific-slope Flycatcher is a migratory bird that nests in Oregon's forests.

Roughly half of Oregon is forest land. The Forest Practices Act and its subsequent amendments placed roughly one-third of Oregon’s forests under sustainable timber production, one-third under multiple-use, and set aside one-third in forest preserves. The act requires any forest use to consider first and foremost environmental impact, including fish and wildlife, clean air and water quality, stream and riparian health, and soil conservation. The application of chemical herbicides and pesticides are strictly controlled to protect fish, wildlife, and people from contamination. Under a 2016 amendment, the act even seeks to enhance wildlife habitat by allowing people to make small open areas in forests to grow food for birds and other wildlife. Other amendments have specifically established regulations that have successfully helped the recovery of owls and bald eagles. Proposals to protect nesting sites of marbled murrelets are presently under consideration.

The fruits of Oregon’s forest stewardship are remarkable. Today, Oregon’s forests are thriving once again. According to the Oregon Forest Resources Institute, Oregon forests are home to some 700 wildlife species, more than 90 of which are found only in the state. Restored forests have gone from being virtual monocultures to being highly diverse in their tree composition and structure, characterized by a mixture of deciduous and evergreen trees and also understory plants that provide flowers, nectar, seeds, and fruits that provide food for wildlife.

These forests include trees of different sizes, from low to high canopy. They include snags and large and small logs left on the forest floor to decay. They offer open spaces and gaps between groves to encourage meadows and provide habitat for birds that prefer heavy cover for nesting but open areas for foraging. To ensure the sustainability of such environments, controlled burns are employed to manage underbrush and reduce the frequency and intensity of wildfires as well as to stimulate the germination of some conifer species.