(Los Angeles Times) Along the saw-toothed ridge of Rattlesnake Canyon, crude graffiti invades the crevices that offered shade to nomadic Indians trekking across the Mojave hundreds, if not thousands, of years ago.

“Skunk,” “oatmeal cookie” and “punx” are scribbled in black spray paint on giant, earth-crushing boulders where ancient petroglyphs may have been etched by the Serrano and Chemehuevi.

The damage goes far beyond a few lovey-dovey teenagers carving their initials into picnic tables. Vandalism in Rattlesnake Canyon and at Barker Dam, two of Joshua Tree National Park’s most popular hiking spots, has been so pervasive that both sites have been closed to the public.

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