Out West student blog

Smoke in the Sierras

Smoke in the Meadows of Yosemite Valley (Photo credit: Emilia Schrier)

By Tish Johnston
English, 2018
Museum Intern
Yosemite National Park

For the past several weeks, my commute from the museum in Yosemite Valley to my home in El Portal has been characterized by a heavy and orange tomato-soup-air that seeps into the car with the distinctive smell of burning forest. This is a regular summer occurrence in Yosemite National Park, but for me the sights, smells, (and sometime fears), brought on by wildfires are all a new experience.

An important thing to understand about wildfires, specifically those in the Sierras, is that they are not all bad and therefore are typically not fully extinguished. Of the six wildfires currently burning in Yosemite National Park (as of August 15, 2017), the fire crews are suppressing only the South Fork fire, while the remaining five are being monitored and allowed to burn. These naturally occurring wildland fires are caused by lightning and allowed to burn because of their ultimate benefits to the surrounding ecosystem. These lands are adapted to burn regularly, both from these natural lighting strikes and 4,000 years of deliberate burns by Native Americans in the Sierras to increase soil fertility and allow new vegetation to grow. Historically all fires in the park were put out immediately, leading to overgrown, unhealthy forests and a dangerous build up of dead plant debris. This accumulated up woody material becomes powerful fuel, leading to large and uncontrollable fires that become a threat. Learn more about fire management practices in Yosemite.

These smaller fires are allowed to burn in order to prevent larger ones and to keep the park’s environment happy and healthy. For now, the orange sky lends its own kind of ominous beauty to August in Yosemite.

However, especially for the outlying gateway communities to the park, fires are incredibly dangerous and lead to the destruction of homes and property. My first experience with wildfire this summer was with one of these menacing blazes. Beginning on July 16, the Detwiler Fire in Mariposa County was doubling overnight to its ultimate size of more than 80,000 acres. The fire caused power outages throughout Yosemite Valley, forced thousands to evacuate, and destroyed 63 homes. Now a month later, the Detwiler Fire is finally approaching 100% containment, but not before leaving families homeless and heavily impacting the economy of Mariposa. Unfortunately, this is only one fire among the droves that threaten communities throughout this region and all of California every year. Here are more details about the Detwiler Fire.

While it may be disappointing to visitors when air quality is too dangerous for strenuous exercise and smoke obscures views of the park’s vistas, these smaller fires are allowed to burn in order to prevent larger ones and to keep the park’s environment happy and healthy. For now, the orange sky lends its own kind of ominous beauty to August in Yosemite.

Read more at the Out West Student Blog »

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