Abstract: Employee #, a trainee with 15 working days experience, was trying to get the front tires of a tractor mower back on the road. A tree branch was under one of the rear tires; he tried to get free of it by moving forward a little bit. Employee #1 did not realize that the manual throttle was still in and put the tractor in forward gear. As a result he lost control of the tractor mower, which jumped the curb and rolled 120 ft down a steep embankment, stopping when it struck an old car. The mower came to rest leaning toward its right side, but never tipped over. Employee #1 was able to dismount the tractor without assistance but was subsequently hospitalized.