A helper and I moved 36' 8x8s on an old car axle last winter. If you are going some distance or have a rough path use ratchet straps to attach the timber to the axle. You can drill a hole in one end of the timber and tie a rope to the timber. Tie the timber to a trailer hitch in a way it can make turns but not flail around and you can tow it around your property.
Also, fixed rollers have there place, but I find wood rollers or schedule 40 pvc pipe rollers to be more useful and affordable.
Never Give Up;
Jim
