I have learned it is better to send a horse than to lead one, I have taught my horse to go where I point. Standing a bit ahead and off his shoulder I point where I want him to go, like in a trailer or over a log or across a ditch. You start with a very short lead line so you can kinda pull him while ointing, wack him in the withers till he moves forward. Teach him than left and right. Work at it alot in the round pen, add some logs and distractions. I did this alot with a horse that refused to load in a slant load trailer with a rear tack room, worked like that daily for a week without even looking at the trailer. Wen to to the trailer and pointed,,, "Go That WaY!" and in he went. I have no doubt I can do the same thing with the ditch. Dunno maybe I should try it. He does still balk occasionally from the saddle but at least he doesnt rear spin around and run the opposite way,, baby steps baby steps.