Unless Congress and the White House can agree on a fiscal package by March 1, workers at Yosemite, Grand Teton, Yellowstone and hundreds of other national parks will have to delay this year's opening and restrict hours of operation.

It’s all part of draconian spending cuts known as sequestration that would also slash military spending, education and unemployment benefits.

Joan Anzelmo, the former superintendent of Colorado National Monument and a spokesperson for the Coalition of National Park Service Retirees, says the National Park Service will have to cut $110 million from a $1 billion budget, five months into the year.

"They will have to not hire seasonal park rangers and other employees," she said. "They will certainly have to reduce hours of operation at some locations — reducing visitor center hours and other kinds of important services such as plowing the roads to get the parks ready to open."

Take the Grand Canyon. While the park is busy now, Anzelmo said, it's should only get busier next month — right when the cuts would kick in.

"Some of the principal roads at Grand Canyon will be closed, and the main visitor center where everyone goes to get information to begin their hike and their experience will also have much reduced hours," he said.

The situation will be the same at Yellowstone, one of the most popular national parks.

"All those gateway communities from West Yellowstone, Mont., to Cody, Wyo., to Jackson, Wyo., to Red Lodge, Mont., — roads won't be plowed, openings will be delayed. All of the gateway communities and the entire economies of those states will be dramatically affected," she said.

The cuts won't just have an impact in those isolated communities. Anzelmo said there would be a hit to the $31 billion the parks pump into the national economy, leading to 250,000 jobs.

"I fear if we were depending on the Congress of today there would be no Yellowstone, there would be no Grand Canyon, there would be no Cape Cod National Seashore," Anzelmo said.

Critics have long claimed the National Park Service is under-funded. Anzelmo says the situation would get worse if the sequester cuts go through.

"I think that the loss of employees, not hiring employees, is going to be a huge impact to the ability of the agency protect the resources, to serve the visitors, to respond to life-threatening emergencies whether someone becomes ill, or heaven forbid, they have a heart attack or an accident in the backcountry, in the mountains, on a remote lake," she said.

Anzelmo pointed out that it could have a major impact on wildfire season as well. Season park rangers and employees, positions that could be at risk, form a major component of the federal firefighting service.

"I think when we think about the national parks they tell our story as a country. They celebrate those victories, but they celebrate some of the shameful parts of our history," she said. "They are interwoven into the entire heritage of all Americans. And I think we ought to channel our inner John Muir and make sure that we protect these incredible places and keep them for another 100 years."