The Keauhou Ranch Fire at Hawai'i Volcanoes National Park was threatening a rare ecological area in the park/NPS

Fires from Wyoming to Hawaii continue to rage in the National Park System, with thousands of firefighters battling flames that are sending billowing, choking clouds of smoke into some parks and limiting access in others. The Yosemite Valley, Wawona area, and Mariposa Grove of Giant Sequoias all remained closed in Yosemite National Park on Thursday.

At Hawai'i Volcanoes National Park, the Keauhou Ranch Fire covered more than 3,200 acres in and around Mauna Loa. Additional firefighters from the mainland and Hawaiʻi were called in and were assisting with suppression efforts.

The fire, which started August 5 outside the park on Keauhou Ranch, had progressed close to the Kīpuka Kī Special Ecological Area and was two miles north of Highway 11 late Wednesday. It was just 5 percent contained.

“We are focusing our suppression efforts on Kīpuka Kī and are working carefully to back the fire up against a natural barrier of wide hardened lava flow so it doesn’t progress further downslope,” said Fire Management Officer Matt Desimone. 

Kīpuka Kī, a Special Ecological Area, is one of the rarest old-growth native forests of its kind in the world, according to the National Park Service. It is comprised of tall ʻōhiʻa, koa and mānele trees that are essential for the survival of threatened and endangered native plant and animal species.

Strong, gusty winds, and dry conditions at the 4,500- to 4,800-foot elevation have made the fire difficult to control with limited resources, and it continues to burn both upslope and downslope on Mauna Loa. The fire started on Keauhou Ranch and its cause is under investigation.

At Yosemite, firefighters had carved containment lines around 79 percent of the Ferguson Fire, which started outside the park last month but had made intrusions along the western half of the park. Crews on Thursday were to focus on holding constructed fire lines and extinguishing hot spots near the fire perimeter. Firefighters also were to have a presence on all portions of the fire, however resources were to be focused on the tunnel area of Big Oak Flats Road, Grouse Creek Drainage, and containment lines leading away from Badger Pass.

At Grand Canyon National Park, the Obi Fire on the North Rim had grown to more than 7,000 acres and prompted the closure of Cape Royal Road, the Cape Final Trail, the Cliff Spring Trail, the northern section of the Ken Patrick Trail from Point Imperial to Cape Royal Road, and the southern section of the Ken Patrick Trail from Cape Royal Road to the old Bright Angel Trail. 

Smoke from the fire was visible from both the North and South Rims of the park. There was also visible smoke being produced by fires on the Kaibab National Forest. Visitors were told that they might see increased smoke or haze filling the canyon. 

At Yellowstone National Park, the Bacon Rind Fire burning along the western boundary north of West Yellowstone was just about 500 acres and not threatening any structures. It was burning in an area that had not burned in the last 150 years and the wildflire had the "potential to clean out the dead and downed trees, and help restore a healthy ecosystem that will be conducive to new growth and create great habitat for wildlife, while reducing the potential for a future large fire," according to a press release.