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Federal Forest Restoration Efforts in Eastern Oregon Have Been Successful, Research Finds |  Oregon

(The Center Square) – Forest thinning efforts have benefited the hardiness of older trees and improved native biodiversity on federal lands in eastern Oregon, University research has found. of Oregon State.

James Johnston of the OSU College of Forestry conducted a study that came to this conclusion. His study involved long-term monitoring and research partnerships between OSU, the United States Forest Service, and local groups in the Blue Mountains region of the state.

The Oregon Department of Forestry estimated the state had spent more than $20 million fighting wildfires as of mid-August 2023, according to Axios.

The results show the collaboration’s success in “attaining federal investments and providing scientific products measuring the effectiveness of forest treatments,” Johnston said in a press release issued by OSU.

“Ecological restoration of seasonally dry, fire-prone forests has been a key goal of Forest Service managers for more than two decades,” Johnson said in the release. “Our study shows that thinning helps restore tree and understory vegetation conditions associated with the ability to rebound from disturbance. And thinning doesn’t just help managers mitigate fire risk – it restores a range of ecological functions that, over time, make forests more resilient.”

Researchers surveyed a 2,900 hectare area in the Malheur National Forest. The study area included the ponderosa pine forests of the southern Blue Mountains; the area has “priority landscape” status and receives money from the Forest Service Collaborative Forest Landscape Restoration Program.

Between 2014 and 2015, this area was thinned in hopes of improving its fire resilience “while facilitating the return of episodic low-severity fires,” according to OSU.

Fire dynamics in the interior of the Pacific Northwest began to change in the second half of the 19th century, according to Johnston.

“The late 1800s and early 1900s were unusually cool and wet,” he said in the statement. “In addition to this, European colonization changed the way indigenous peoples used fire in the landscape – that is, settlers did not want fires on their land and early rangers put out fires. aggressively started fires in the name of sustained yield timber harvesting This was extensive, unregulated grazing that eliminated the fuel responsible for low-severity surface fires.

In the late 20th century, dense stands and shady understory caused “high-severity wildfires, unusually severe drought-related mortality, and susceptibility to bark beetles,” the statement said. That said, forests were less resilient than before.

Johnston and his research team have quantified the extent of thinning that can restore forest resilience. They examined attributes of overstory trees, including radial growth, resin production, abundance of nonstructural carbohydrates, and leaf area.

“We also studied the responses of understory vegetation – grasses, herbaceous plants and shrubs that influence fire behavior and forest resilience,” Johnston said. “We found an increase in species richness and diversity in thinned stands three to four years after thinning, which stimulated the growth of vegetation that tolerates low-intensity fire regimes and is suppressed under closed canopy forest.”

Researchers found that tree radial growth was higher in thinned stands three years after thinning began. They also found that the presence of glucose and fructose was lower in the treated stands, “suggesting that the trees were using their carbon stores for leaf and wood production,” the statement said.

“And even though our study area has not been treated with prescribed burning, we view fire reintroduction as an important management tool that can restore historic fire regimes and achieve additional management goals,” said Johnston in the release.

The study received funding from the Forest Service through the Collaborative Forest Landscape Restoration Program, the National Institute of Food and Agriculture, and Blue Mountain Forest Partners.