TACOMA — Karen Strand didn’t think she’d get in trouble for having a small container of medical marijuana when she went hiking in Olympic National Park this summer.

President Barack Obama, she remembered, had said the federal government had “bigger fish to fry” than people who follow state marijuana laws, and Washington state had just legalized pot.

But a ranger pulled her over on a remote gravel road, and Strand wound up as one of at least 27,700 people cited for having pot on federal land since 2009, according to an Associated Press analysis of federal court data. The number of citations is small compared to the hundreds of millions of visitors to national parks, forests and monuments each year.

But it nevertheless illustrates one of the many issues Washington, Colorado and other states face in complying with last month’s Justice Department memo that requires them to address eight federal law enforcement priorities if they want to regulate marijuana. Among those priorities is keeping marijuana use and possession off federal property.

State officials have no plans to license pot gardens or stores on federal land, but beyond that, they say, it’s not clear what they can do to discourage backpackers or campers from bringing a few joints into Rocky Mountain or Mount Rainier National Park.