Changes

Experts say these long-term changes create a special risk in Pacific Northwest forests: Even a modest increase in contributing factors, like days without rain, could make them much more prone to burning.

“Those are the kinds of changes that amount to taking a forest and pushing it over the edge,” said Michael Medler, a fire scientist and chair of Western Washington University’s environmental studies department.

Exactly when any one part of the region will reach that point is hard to predict, and researchers stressed that unknowns exist in forests that have burned so infrequently in the past. But all pointed to changes already taking place.

For instance, the region’s fire danger this year reached above-normal levels three months earlier than at any time in more than 10 years, driven partly by an abnormally dry winter.

And fire counts are up: As of late June, western Oregon forests had seen double the average number of fire starts from the previous decade — 48 compared with 20. Washington jumped even further, with 194 starts compared with an average of 74.

Even the region around Astoria, Oregon, which frequently gets 100-plus rainy days per year, has seen a dozen small fires in 2018 and 2019, according to data from Oregon’s Forestry Department. That compares with an average of just two per year over the previous decade.

Last year, 40% of Washington’s wildfires were on its wetter western side, which was “alarming and a first for us,” Janet Pearce, a spokeswoman for that state’s natural resources agency, said in an email.

The risk is amplified by development patterns throughout the Pacific Northwest.

A 2013 Headwaters Economics survey of development within 550 yards (500 meters) of forestland found that just six counties along the western foothills of Washington’s Cascade mountains host more homes in such zones than all of California.

Ray Rasker, who heads the nonprofit land management research group, cautioned the report was narrower than others — which count development up to 1.5 miles (2.4 kilometers) from any wildland — and other types of wild areas are more prone to burning than mature forests.

But while officials in California and other states have begun reforming forest-edge building and landscaping rules, such codes are rare in the Northwest, and virtually none apply to houses already built, said Tim Ingalsbee, who heads Firefighters United for Safety Ethics and Ecology, an Oregon-based nonprofit that works to update building codes.