AYESHA RASCOE, HOST:
Rock stacking may seem like a wholesome way to leave your mark on a trail. Known as rock cairns, they've been used as navigational guides and memorials in parks and by rivers. But some park officials want you to stop stacking them. Rangers at the Dinosaur Valley State Park in northeast Texas say that they can disturb the habitat of many small aquatic creatures like frogs and insects.
ALLEN DEES: Removing those habitats, we lose that major service of being able to just determine how clean the river actually is.
RASCOE: Ranger Allen Dees works at Dinosaur Valley State Park. He says that while rock cairns are used as guides for hikers in other parks, that's not the case at his park. So stacking rocks could cause confusion.
DEES: ...Which can result in us having lost or missing hikers as a result. They could go into a very sensitive environment down on the trails.
RASCOE: Ultimately, Ranger Allen wants visitors to remember the hiking etiquette known as leave no trace. It's comprised of seven principles, like planning ahead and respecting wildlife.
DEES: And they all focus around the main concept of leaving it better than you found it.
RASCOE: That's Ranger Allen Dees of Dinosaur Valley State Park.
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