There are ways to load logs onto trailers with small tractors like looping a chain over the log, hitching it to the trailer and rolling the log up two beams by pulling the chain across the trailer. It's easy on the tractor and pretty safe. However, if you're intending to pick up the logs using forks mounted on a front end loader then you need a big tractor. A little 30-40 HP machine isn't going to go toting around 20" logs of any length. You're expecting too much of a tractor of that size and you're risking your neck also. Go to any sawmill and see what they pick up sawlogs with, it ain't a 40 HP tractor I can assure you. You need a LOT more tractor for what you're wanting to do.