Vandalism along the Whychus Creek Trail has caused erosion into Whychus Creek, the Deschutes National Forest reported Monday.

One or more vandals dug 11 boulders out of a steep bank below the trail and then pushed the large stones down an embankment, creating unstable soil, according to the national forest. A volunteer discovered the damage about a week ago. Since then, Sisters Ranger District workers have been out to the creek to assess and repair some of the vandalism.

The trail near Sisters was built in 2011 and passes along a federally designated wild and scenic portion of the Whychus Creek.