Investigators haven't determined the cause of a wildfire that burned about 4 1/2 acres Wednesday evening near a Wallowa-Whitman National Forest campground along the South Fork of the Burnt River about six miles southwest of Unity.
No lightning, which starts about 80 percent of the blazes on the Wallowa-Whitman, has been reported in that area for many days, said Renae Crippen, manager at the Blue Mountain Interagency Dispatch Center in La Grande.
The lookout working at Table Rock, several miles south of the campground, reported the fire at 6:10 p.m. Wednesday. A private citizen in the area also called in the blaze, at 6:23 p.m.
Firefighters from the Forest Service and the Oregon Department of Forestry, along with two bulldozers, stopped the fire's spread Wednesday night.
A single-engine plane from John Day dropped one load of retardant before night fell, Crippen said.
Crews are mopping up the fire today.
Although forests and rangelands are extremely dry, prompting a variety of restrictions on campfires, motor vehicle travel and the use of chainsaws, the region has been relatively lucky in that lightning has been rare since mid-July, Crippen said.
That luck might be about to change, though.
The National Weather Service is forecasting a chance of thunderstorms this weekend and into early next week.