Rubs - purpose?

[Tom Anderson]

Are rubs on trees used by a buck to mark his territory or do they just rub trees at random to get the velvet off?

[fireball31]

Both.  During the rut a deer with a polished rack will still make rubs to advertise his presence.

[trapperDave]

and build his neck muscles

[Dave2old]

Fireball has it right. Those slits below the eyes -- suborbital glands -- secrete scent-laden "sebacious" fluids that identify specific bucks and bulls to others of their kinds. Whether this is an actual territorial marking is in doubt; more likely just an "I've been here ... and here ... and here!"

[Tom Leemans]

and does will be more receptive to a handsome big fella with a nice looking rack. I personally watched a doe hanging around a fresh rub until a buck showed up the other night. Nature has it figured out.

[Blackhawk]

Biologists say bucks do this because there are no bars open that serve drinks to deer.