Abstract: At 10:30 a.m. on July 4, 2023, an employee was operating a John Deere ZTrak Pro Series Gas Z915B 54-inch zero-turn riding mower to cut grass on the hillside located between the driveway into the property and the creek to the east of the driveway. The employee drove the mower up the hillside (north) in the grass along the driveway and made a right turn at a utility pole at the top of the hill. The mower apparently lost traction on the hillside, and the employee could not control the mower to make it go parallel to the creek. Instead, the mower went forward down the hillside (eastward) toward the creek. At the creek's embankment, the mower struck a tree. The employee separated from the mower and landed face first on a rock in the creek, and the mower fell off the embankment into the creek, flipping over and landing on top of the employee. At the time, the employee did not wear the mower's seat belt and did not have the mower's rollover protective structure extended (unfolded). The employee was killed due to compressional asphyxia.