The 2021 Lick Fire burns at night in the Umatilla National Forest, Oregon. USDA Forest Service photo by Brendan O’Reilly.
Hot, dry air conditions fuel more intense wildfires, while cool, moist air conditions can make fires easier to manage.
Quercus rubra showing evidence of advanced root decay caused by the pathogen Armillaria gallica in Georgia, USA. USDA Forest Service photo by John W. Hanna.
Armillaria root diseases are a major cause of mortality and reduced growth of trees in forests worldwide. Trees stressed by drought, high temperatures, and other environmental stressors may be predisposed to Armillaria infection.
Xavier Lee, an intern with the Pacific Northwest Research Station, measures the diameter of a tree burned in the 2020 Archie Creek Fire, Oregon. USDA Forest Service photo by Morris Johnson.
Large, stand-replacing wildfires are expected to become increasingly common due to climate change, but there are limited scientific data available to help managers evaluate options for forest management after wildfire.
A prescribed burn conducted in the Fishlake National Forest, Utah, in 2020. USDA Forest Service photo by Roger Ottmar.
Led by scientists Roger Ottmar and Sim Larkin with the Pacific Northwest Research Station, the Fire and Smoke Model Evaluation Experiment (FASMEE) is a large-scale, multiagency effort designed to identify how fuels, fire behavior, fire energy, and meteorolog
A view from the Buckhorn Wilderness in the Olympic National Forest, Washington. Coastal forests in the Pacific Northwest store globally significant amounts of carbon in trees and soil. USDA Forest Service photo by Matthew Tharp.
Urgency is growing among legislators, conservation organizations, and the wood products industry to better understand how forests store carbon and how management choices affect the carbon balance. The Pacific Northwest Research Station is taking a convening role with states and nongovernmental organizations to address research needs across stewardship boundaries.
A researcher in Saipan, the largest of the Northern Mariana Islands, examines a tree infected with brown root rot. Photo courtesy of Ned B. Klopfenstein.
Mango, breadfruit, and many other tropical fruit trees are susceptible to brown root rot caused by the invasive, deadly pathogen, Phellinus noxius.
An air resource advisor adjusts an air quality monitoring station during the 2019 Milepost 97 fire near Canyonville, Oregon.
Smoke from wildland fire is responsible for most of the hazardous air quality days across the country. As a result, millions of people are exposed each year to unhealthy air quality, according to the Environmental Protection Agency’s National Ambient Air Quality Standards.
Helicopter dropping water on the Maple Fire in the Olympic National Forest. USDA Forest Service photo.
It’s easy to assume that the forests on the western side of the Cascade Range are too wet to burn, but that’s changing. These lush coniferous forests are legendary for their beauty, timber growth rates, and the habitat they provide for iconic species of the region. Historically, ample rain and winter snow kept these Pacific Northwest forest moist throughout much of the year.
A field of scotch broom. USDA Forest Service photo.
Scotch broom (Cytisus scoparius) is an invasive shrub that thrives in sunlight and quickly colonizes bare ground. Managing Scotch broom in Douglas-fir plantations is a priority for many forestland owners in the Pacific Northwest because this noxious weed competes with Douglas-fir seedlings for nutrients and water. And Scotch broom seeds appear to remain viable in soil for decades.
The orange pitch tube and frass at the base indicate red turpentine beetle attacked this fire-damaged tree near Sisters, Oregon. USDA Forest Service photo by Doug Westlind.
In ponderosa pine forests of western North America, wildfires are becoming more frequent and affecting larger areas. Prescribed fire is increasingly used to reduce fuels and mitigate potential wildfire severity. Both fire types damage trees that initially survive their burn injuries but eventually die.