Viewer, Patrick Wickwire

The Gnarl Ridge Fire shown here in a viewer photo, put up a smoke plume on Saturday that was visible for miles.

PORTLAND, Ore. - A wildfire on Mount Hood was threatening some historic structures and some area residents were warned to have an evacuation plan.

The Gnarl Ridge fire on the north side of Mount Hood expanded to 800 acres Saturday, prompting officials to call for more firefighters and protect the historic Cloud Cap Inn and Tilly Jane campground.

About 415 firefighters were battling the lightning-sparked blaze.

The U.S. Forest Service on Saturday warned Cooper Spur residents with special needs that they should develop an evacuation plan in case the fire spreads.

The high temperatures of recent days have sparked many spot fires, making it tough for crews to maintain fire lines, officials said.

In Eastern Oregon, fire crews were working a 100-acre blaze on the west side of Oregon 395, near Ukiah.

The Camas Knob fire was burning in timber, brush and grass on lands protected by the Oregon Department of Forestry.