At a time when snowpack is below normal across much of the West prompting concerns of wildfire danger and a lack of spring runoff, a new study shows more refined forest management practices can optimize for both wildfire resilience and snowpack. 

Forest managers currently use controlled burning and the selective felling of trees as ways to thin forests. Both methods remove fuel and help return tree stands to historical conditions — but less is known about their impact on snowpack. 

To address the knowledge gap, a team of researchers at the University of Washington (UW) and The Nature Conservancy embarked on a multiyear study of snowpack along Cle Elum Ridge, an area of the eastern Cascade Mountains in the headwaters of the Yakima River Basin. The group experimentally thinned a 150-acre area of the forest to varying degrees. Then, it measured the amount and duration of snowpack during the winter of 2023 and compared it to a previous winter before the forest treatment.  

The results were encouraging. Forest thinning efforts increased snowpack by 30 percent on north-facing slopes and by 16 percent on south-facing slopes. Thinning aided snowpack the most where it created a patchwork of gaps in the forest rather than a more even density; gaps of 4-16 meters in diameter seemed to be the “sweet spot” for snow.  

“At its core, this research shows that reducing wildfire risk and protecting water resources don’t have to be competing goals,” said lead author Cassie Lumbrazo, a postdoctoral researcher at the University of Alaska who completed this work as a UW doctoral student. “That’s genuinely good news for a place facing both growing wildfire threats and increasing water vulnerability. So much of the climate conversation focuses on loss, which makes findings like this especially meaningful.” 

Study authors found one surprising result. They maintain the way forest managers thin forests does not reliably create gaps in the canopy. Forest managers map out their reductions using the density of trunks in an area, not canopies, as their primary measurement. 

“Imagine a group of 100 people all holding umbrellas in the rain,” said co-author Susan Dickerson-Lange, director of the UW Climate Impacts Group. “They’re standing close enough together that their umbrellas overlap, so none of the rain hits the ground. If you remove 10 of the umbrellas randomly, you’d still have plenty of coverage overall. But, if you remove 10 umbrellas that are right next to one another, you create a gap in the umbrella ‘canopy,’ and you get a 10 percent increase in the amount of rain that hits the ground.” 

The work could also aid collaboration between forest managers and hydrologists at a time when the region needs all the water it can get. 

Hunt 2 Conserve is a strong proponent of active forest management to improve wildlife habitat and forest health, reduce the risk of catastrophic wildfires and better protect public safety.   

Click here to read the entire University of Washington news release and view imagery and a video about the research. 

About Hunt 2 Conserve 

Hunt 2 Conserve is a 501(c)4 nonprofit organization affiliated with the Rocky Mountain Elk Foundation. Its mission is to advance a legacy of hunting and conservation by educating, activating and developing stewards and defenders of these fundamentally American ideals. For more information, go to hunt2conserve.org. 

(Photo credit: Mark Stone/University of Washington)