Melinda Rich Marshall pointed her white S.U.V. toward a billowing tower of smoke on Tuesday and gunned it down the now-empty roads leading to the charred North Rim of the Grand Canyon.

A few days earlier, she had joined hundreds of tourists and seasonal employees who fled a wildfire roaring through the parched sagebrush and ponderosa pines. Now, she was headed back to check on the Jacob Lake Inn, her family’s 102-year-old lodge just outside Grand Canyon National Park.

“We don’t know how we’ll pay our employees,” Ms. Marshall, 43, said, looking toward months or years of economic losses as the park rebuilds from one of the most destructive fires in its history. “What do we do? How do we live?”

Residents like Ms. Marshall, along with Arizona’s political leaders, are asking why the Dragon Bravo fire, sparked by lightning on July 4, was allowed to burn for days in hot, dry conditions before it exploded beyond containment lines and tore through the heart of the North Rim. Some are also demanding to know whether the Trump administration’s budget freezes and Forest Service layoffs could be playing a role, not just at the Grand Canyon but at fires raging around national parks in Colorado and Washington as well.