Snow melts and becomes water, and the newly heated water becomes vapor as piles of dry wood and other plant debris start to burn slowly when firefighters, one after another, dip their drip torches.
Winter is the ideal time of year for pile burning on national forests and it’s one of the many ways the USDA Forest Service works to remove excess debris and lower fire risks to communities in advance of wildfire activity each year.
As winter conditions continue across the US, some national forests create hundreds of “slash piles.” These piles are waiting to be prescribed burned because, throughout the year, fuels reduction and hazardous tree removal projects have been completed.
Fuels reduction involves mechanical and hand thinning, meaning that dead, dying or excess trees are removed to reduce forest density and improve forest health. Larger diameter logs are removed for use in building materials; limbs, brush and other small forest woody debris are then piled up for burning in the winter when it is most often safest to do so.
The piling on, if you will, begins when crews thin the forest using chainsaws or traditional handheld saws and then pile the scraps of wood. Another process, mechanical thinning, uses heavy equipment to create piles as well, albeit a little larger in size.
Burning the piles must be done under specific, “prescribed” conditions. Wind direction, snow cover, adequate staffing, precipitation and temperature all play into the decision to dip the flaming drip torches--or not.
It’s important to note, though, that even with the most thorough planning and preparation, the use of prescribed fire carries an inherent level of risk that cannot be eliminated entirely. At the same time, prescribed fire is one of the most efficient and effective ways to reduce wildfire risk. Regularly conducting low-grade prescribed fires, which mimic nature, reduces the buildup of flammable vegetation and overgrowth.
Other criteria considered before lighting a prescribed fire include:
Prioritizing piles based on proximity to communities, elevation and the ability for heavy equipment and firefighting personnel to easily access the site to control any unexpected situations.
Alerting the public that pile burning and the often visible flames and glowing embers are a normal part of the process.
Working to avoid any unnecessary smoke drifting over nearby communities. Snow helps contain the piles and firefighters monitor the area during and after the burn.
Understanding that public and firefighter safety is always the priority during burning operations.
The Forest Service and its partners at the federal, state and local levels work to balance air quality and public health considerations when pile burning. For more information about Forest Service efforts to improve forest health and resilience and reduce wildfire risk to communities visit: Confronting the Wildfire Crisis | US Forest Service (usda.gov).
