6-10 ft high is to high for a deer. Did they look fresh? Could be a moose rub line from last fall or real early spring when they are dropping the antlers. It would look like scratches or will have hair in it. If it was a bear and rubbed right down to smooth wood if from antlers. Hard to tell with out a picture..... I hope this helps
This is a moose rub but they are not always this big
http://wildwoodtracking.com/mammals/...lerrub3878.jpg
This shows a bear rub and scratches
http://www.nrmsc.usgs.gov/research/N...jectPhotos.htm