Lovers of the United States' landscape, wildlife, and parks will feel the pain of mandatory spending cuts set to take effect this Friday, warn leaders of the nation's land agency.

At a press conference just days short of the March 1 deadline, Jonathan Jarvis, director of the National Park Service, and Interior Secretary Ken Salazar, outlined how so-called "sequestration" will hurt the country in general and national parks in particular. (See pictures of the top ten national park landmarks.)

1. Hits to the national wallet. The national parks return more than $10 for every dollar invested by the taxpayer, Salazar pointed out. The park system is a profit center as productive as any in our economy. In 2011, Maine's Acadia National Park drew 2.4 million visitors, contributed $186 million to the state's economy, and supported 3,000 jobs. Yellowstone National Park drew 3.4 million visitors, contributed $333 million, and supported 5,000 jobs. Everglades National Park drew 934,000 visitors, contributed $147 million, and supported 2,400 jobs. And these are just three of the 398 national parks, monuments, memorials, reserves, preserves, historic sites, seashores, lakeshores, and battlefields across the country.

"In 2011," summarized Salazar, "279 million visitors came to our national parks, pumped 30 billion dollars into the economy, and supported 252,000 jobs."

The report for 2012, just out, shows that park visitation grew by three million, to 283 million.

The park system is also doing its part to address the U.S. trade imbalance. Last year, according to Salazar, the parks drew 62 million international visitors and $152 million in foreign capital. International visitors stay longer in the parks and spend more.

Before the specter of sequester rose, the Park Service set a goal of attracting a hundred million foreign visitors by the end of 2021. (See National Geographic's recommendations for the best national park hikes.)

The sequester will require a 5 percent cut in the budget of each park. While this might not seem like a devastating percentage, the secretary said, in fact it would strike at the heart of the limited discretionary funds available to the Park Service.

In the context of the Department of Interior as a whole, he said, it would be like closing down the entire Bureau of Land Management.

2. Campground and cave closures in the Southeast. As examples of the belt-tightening required of every park to achieve a 5 percent cut, Director Jarvis picked the Great Smoky Mountains National Park, where five campgrounds and picnic areas will be closed; the Blue Ridge Parkway, where seven contact stations will shut down; and Mammoth Cave National Park, where a portion of the cave tours will be eliminated. That may be good news for the bats, but not for the hundreds of thousands of visitors who explore these caverns each year.

3. Unhappy kids in the Northeast. At Cape Cod National Park, the Provincetown Visitor Center will be closed. At Independence National Historical Park, the interpretive program will be cut in half.

"And at Gettysburg," said Jarvis, "this year being the 150th anniversary of the Battle of Gettysburg, we'll be reducing our education programs. Twenty-four hundred kids from the towns in the area will not be able to participate." (See vintage photos of the national parks.)

4. Empty silos in the Midwest. The Minuteman Missile Site in South Dakota will close all tours, turning away 50,000 annual visitors. The Cold War, in that sense, will grow a little colder.

5. Snowy park roads in the West. The month of March, just as the sequester would hit, is when many parks open. It's also when the National Park Service hires "seasonals," the men and women who fight fires, provide extra law enforcement for peak months, and do search-and-rescue-hiring that will have to be curtailed. Also in March, water systems are reactivated and snowy roads are plowed.

"In the Rocky Mountain region, in Yellowstone and Glacier, we will be delaying plowing of the roads to open those up, sometimes as much as a month," Jarvis said.

"That delay will have a direct impact on gateway communities around Cody or Jackson Hole, or up in Glacier at Whitefish. The communities there, they know their season starts the day the roads open and closes the day the roads close. That can be as much as a million dollars a day lost to the local economy."

At Grand Teton National Park, the Jenny Lake Visitor Center will close. In Yosemite, plowing of the Tioga Road, a principal route over the Sierra Nevada, will be delayed, affecting 2,000 to 3,000 travelers a day. Delays in plowing the road to Wonder Lake, in Alaska's Denali National Park, will affect as many as 4,000 visitors a day.

6. Thistles and pythons and carp and wild boars. Jarvis reminded the press that national parks need constant defending from invasive plants and animals. Funding cuts will compromise control programs throughout the park system, he said, including efforts to remove yellow star thistle from Yosemite, Burmese pythons from the Everglades, and feral pigs from Hawaii Volcanoes National Park.