GETTYSBURG, Pa.—In Pennsylvania, some of the nation's most famous national parks are bracing for the automatic budget cuts that could soon put a noticeable crimp in their operations.

A National Park Service memo obtained by The Associated Press says that Gettysburg National Military Park would lose nearly 7,000 volunteer hours because of a lapse in volunteer coordinators.

The document also says Gettysburg would be less able to address invasive species and would cut 20 percent from its student education programs.

At Independence National Historic Park in Philadelphia, the Park Service is considering closing half the 16 interpretive sites in spring and fall.

The showdown between President Barack Obama and congressional Republicans could trigger $85 billion in automatic cuts if a deal can't be reached before March 1.