Eagle Cap Wilderness fires grow

Aug. 31—The Wallowa-Whitman National Forest has closed sections of three trails that are near one of the two growing lightning-sparked fires the agency is monitoring in the Eagle Cap Wilderness northeast of Baker City.

The Wallowa-Whitman announced the trail closures, in the North Minam River area, on Tuesday, Aug. 30.

Both the Sturgill fire, which is near the closed trails, and the Nebo fire, more than 15 miles east on the opposite side of Oregon's biggest federal wilderness, produced large smoke plumes on Tuesday as temperatures eclipsed record highs for the date.

The fires started Aug. 22.

The Sturgill fire, estimated at 1,000 acres on Wednesday, Aug. 31, spawned a pyrocumulus cloud Tuesday afternoon and evening — in effect, a thunderhead induced by the fire's heat.

On Wednesday afternoon, Aug. 31, both the Sturgill and Nebo fires generated pyrocumulus clouds.

The atmosphere was already slightly unstable Tuesday, meaning the sun was heating the ground and causing the air to rise high enough that some of the moisture condensed into cumulus clouds, said Jay Breidenbach, a meteorologist at the National Weather Service office in Boise.

The fire added considerably more heat to the equation, he said, allowing the air to rise even higher. The result was the pyrocumulus cloud.

Breidenbach said he reviewed a time-lapse loop of satellite images from Tuesday, and the progression of both smoke from the Sturgill fire, and the formation of the pyrocumulus cloud, were evident.

Such clouds typically form late in the afternoon and dissipate relatively rapidly after sundown as the air cools, Breidenbach said.

Wallowa-Whitman fire managers said they expected both the Sturgill and Nebo fires would generate smoke plumes both Tuesday and Wednesday, which was forecast to be even hotter, said Matt Burks, public affairs officer for the Wallowa-Whitman.

A press release from the forest on Tuesday afternoon stated that the Sturgill and Nebo fires are having beneficial effects by reducing the fuel load and creating a "mosaic" pattern of heavily and lightly burned areas, as well as areas that don't burn.

"This range of fire effects is expected and desired," the press release states. "As temperatures increase (and) humidity decreases this week, fire activity on the Nebo and Sturgill Fires is expected to increase and large smoke columns or plumes may be visible from nearby areas."

Although Wallowa-Whitman officials are monitoring the fires, as they have done with more than 30 lightning-sparked blazes in the 365,000-acre Eagle Cap over the past quarter century, fire managers intended to have helicopters drop buckets of water on both the Sturgill and Nebo fires today to try to curb their spread in certain directions.

Todd Pederson, an assistant fire management officer on the Wallowa-Whitman, said the goal is to keep the Sturgill fire from crossing the Minam River, and with the Nebo fire the objective is to prevent flames from spreading into the upper Imnaha River drainage.

Pederson said on Wednesday morning that both fires are behaving about as fire officials expected.

Among the criteria that officials use to determine whether to monitor or fight a fire is its proximity to private property and to the wilderness boundary.

As a current example, Pederson cited a fire reported on Tuesday, but confirmed on Wednesday in the upper Lostine River area, where a road corridor penetrates into the wilderness for several miles.

Because that fire is near the wilderness boundary, the Wallowa-Whitman is treating the blaze as a regular fire, and trying to put it out as soon as possible, Pederson said.

Firefighters rappeled to the fire on Wednesday, and air tankers dropped retardant, he said.

Sturgill fire

The blaze, on the east side of the Minam River Canyon, is about 6 miles from the nearest private property. There were initially two separate fires in the area, but they have burned together, Burks said.

Firefighters are working on a strategy to protect private land at Red's Horse Ranch and Minam River Lodge to the northwest.

The Wallowa-Whitman has closed sections of three trails near the fire.

—Minam River trail, No. 1673, from the Bear Mt. trail junction south to the Rock Creek trail.

—North Minam trail, No. 1675, from the Minam River trail to the Bowman trail.

—Green Lake trail, No. 1666, from the North Minam trail to Green Lake.

Nebo fire

The fire was estimated at 800 acres on Wednesday, Aug. 31. Firefighters are working along roads and trails outside the Eagle Cap Wilderness to potentially use them as control lines if necessary to protect the Lick Creek Guard Station, structures at Big Sheep Camp, and Indian Crossing campground along the Imnaha River should the fire threaten those, according to the Wallowa-Whitman.

There were no trail closures around the Nebo fire as of Wednesday, Aug. 31, but Pederson said officials were planning to temporarily close the roads leading to the Tenderfoot and Lick Creek trailheads.

Crockets Knob fire

This blaze, started by lightning on Aug. 22, continues to burn on the Malheur National Forest, in the Greenhorn Mountains about 19 miles north of Prairie City.

The fire has burned about 1,900 acres. Gusty winds and higher temperatures on Tuesday, Aug. 30 resulted in active burning, and the fire produced a significant smoke column.

The fire has moved close to the west Princess trailhead south of Indian Rock Lookout, and it has spread northeast onto a small part of the Umatilla National Forest.

Hot Shot crews are working on the east side of the fire, as well as in the roadless areas to the north and west, building and plotting containment lines.

On the southern flank, crews have blocked the fire in the Big Boulder Creek area.

Aircraft, including helicopters dipping water from Olive Lake to the north, continue to work on the fire.