BEND, Ore. -

A “holdover smolder” from the Fourth of July fireworks show ignited near the summit of Pilot Butte Saturday morning, burning about a half-acre of the northeast Bend landmark before crews could contain it, officials said.

Firefighters responded around 5:15 a.m. to the report of a brush fire on the northeast side near the summit of the 4,140-foot, brush-covered butte, a popular state park, hiking spot and viewpoint from which the yearly fireworks show is lit, said Bend Fire Battalion Chief Dave Howe.

They arrived to find about a half-acre burning, with winds pushing the flames down the hill to the northeast, Howe said.

Crews were able to contain the fire at about that size, with assisting engines from the Deschutes National Forest and Oregon Department of Forestry, he said.

Howe said the fire offers a reminder to all that if you use fireworks, be sure the entire area is free of any smoke, hotspots, embers or fireworks debris. He also urged using “a liberal amount of water to ensure that the brush will not ignite.”

Coincidentally, the yearly show’s grand finale was scaled back this year, leaving out the biggest, 8-inch mortars, after Bend fire inspectors visited the site Wednesday and told fireworks organizers they had not properly secured the mortar troughs with sand -- a requirement by the state fire marshal when mortars are electrically fired.

Bruce Lawson, owner of Homeland Fireworks, told The Bulletin (which co-sponsors the display with Bank of the Cascades) that in nine years of organizing the show, he’d adhered to federal regulations that allow the mortar troughs to be used without sand or soil.

Lawson told the paper he’d never been confronted about the state regulation before. Word of the issue just one day before the show did not leave enough time to resolve the issue.

Larry Medina, deputy chief of fire protection, said sand or soft soil are required to absorb a shell blast in case one misfires in the tube. Using the butte’s cinders, he said, could lead in the event of an explosion to dangerous shrapnel to those setting off the fireworks display.