THE DIRT

By Rob Ribe, FASLA, PhD

I recently joined with landscape architecture faculty colleagues Bart Johnson, David Hulse, and Chris Enright, along with other scientists, in a study of wildfire risks in the southern Willamette Valley of Oregon. Our National Science Foundation project employed complexity science to simulate prospective landscape change and wildfire scenarios over fifty years. We simulated landscape change scenarios many times across an actual large area. The factors that influenced the simulations were different climate projections, consequent vegetation changes, likely behaviors landowners told us they would engage in, and fire behavior.

Very few of our numerous 50-year simulations suggested the likelihood of as many simultaneous, intense, and extensive wildfires as were seen in western Oregon in the first two weeks of September. This suggests the incidence of large and severe wildfires in the West is not linearly related to advancing climate change, as we and others have thought. With a warming climate, there may be more of an exponential, but still variable, growth in the incidence of large, and often simultaneous, very costly wildfires.

The extensive intensity of increasingly frequent wildfires promises to consume ever more forests, lives, and property in out-of-control ways, overpowering conventional wildfire prevention, amelioration, and suppression measures.

Outbreaks of multiple hazardous and simultaneous wildfires happen when several regional factors converge to produce “blowtorch” conditions. These can include extremely dry fuels (after months of drought), high temperatures, very low humidity, high winds, accumulated fuel loads, and forests stressed by advancing diseases and mortality. The resulting wildfires often exceed those of historically natural ones. Those natural wildfires tended to foster forest health because they often burned with less intensity, more variable intensity across landscapes, and less average overall acreage.

The only effective long-term solution is to reverse climate change, which will not slow down in the near term. But in the meantime, forests can be managed to be more resilient to fire.

Fuels reduction is the only known option to increase forests’ resilience. Prescribed portions of young or smaller trees, dead wood, and shrubs could be reduced in hundreds of millions of acres in the American West, and again, later on, in the forests of the eastern states. This is happening at a growing pace, but piecemeal, wherever funding and political support coalesce. It’s not enough to meet the larger challenge.

Sporadic projects tend to occur near suburban or exurban areas where risks are appreciated due to recent wildfires. In national parks, legal mandates promote the restoration of native, low-fuel ecosystems by prescribed fire, another method of fuels reduction. Badly burned forests must be replaced by more fire-adapted forests, but this is rare.

The implementation of an adequately extensive forest fuels reduction program is beset by ideological blame-shifting and politically prohibitive costs. There is also a shortage of well-trained professionals dedicated to this task, who can manage risks and build support for projects by sensitively and creatively engaging with local landowners and communities.

Conservatives deflect blame to scientific managers and conservationists by asserting that most forests have been “mismanaged” because they have not been freely and widely commercially thinned and harvested for wealth production at no cost to taxpayers. Ecologically-oriented environmentalists deflect blame to conservatives by asserting that most forests have been “mismanaged” because they have not been managed to emulate natural processes, like prescribed fire, as opposed to ecologically-destructive management geared only toward short-term profits. Everyone else is to blame in such incendiary partisan narratives: No one takes responsibility to fix the problems or bear the costs.

This broad, divisive notion of “mismanagement” is vexing. People dealing with real forests in real places can rarely identify a simple and obviously correct management approach. There are always questions of what, why, where, and when in decisions about budgets, biological systems, interacting and conflicting goals, alternative techniques, public and logger safety, wildlife, amenities, and the politics of local and regional stakeholders. Fuels reduction must be a major goal, but the best way to achieve this must be carefully tailored to each forest in its social and ecological context.

There will be forests where commercially profitable fuels reduction is appropriate, but there are many where this will be impossible, because costs exceed the value of marketable products.

There will be forests where prescribed fire is appropriate and efficient, but not everywhere. Numerous homes have been built within many forests. This makes prescribed fires more difficult to execute. Homeowners are often averse to perceived or actual risks, the intentional production of smoke, and changes to landscape amenities.

Climate change is also reducing the frequency and duration of weather conditions and fuel moisture levels required for safe prescribed fires. Prescribed fire is also difficult to safely control in increasing areas of forest with many weak or dead trees. If poorly planned, fuels reduction can impose risks to long-term forest health, net carbon sequestration, wildlife habitats, soils, biodiversity, and long-term sustainability of local timber or recreation economies; and it can’t be universally implemented.

A national program of extensive, well-planned forest fuels reduction and increased carbon sequestration would be very costly. Forest landowners are already shouldering growing insurance costs. It would require bipartisan, constructive, sustained, and large investments in public forest capital.

A complete, valid, and public GIS database of forest conditions in all western states must be rapidly created and maintained.

A private-public partnership with a clear mandate to foster forest health and resilience would need to award funds and coordinate and enable work across states, localities, landowners, and agencies. New, well-crafted rules would need to set fuels reduction and carbon sequestration goals with strong performance standards. These must clarify how projects must not be cheap and quick, but locally-appropriate to produce long-term forest health and beautiful, diverse forests.

Professional local planning, public participation, honest environmental reviews, and carefully proficient implementation would all be imperative.

Rob Ribe, FASLA, is professor and director of the master’s of landscape architecture program in the department of landscape architecture at the University of Oregon. He holds a master’s degree in landscape architecture and a PhD in land resources. Ribe was a lead scientist in studying the social acceptability of timber harvests and forest planning in the Pacific Northwest following the spotted owl controversy. He has also studied private landowners’ forest management choices.