I went camping for a couple of days and during the process of moving my camp from an isolated spot to one more habitated, my mare backed out of the trailer so fast that she over stretched and shredded her bungie-type trailer tie. Luckily it didn't break all the way thru and pop her in the face or she'd still be running. A Lady there said she never ties her horses heads. They self-load and she just fastens the latch.. I tried that coming home (my mare loads easily.. self-loaded this time) but when we arrived home, with no head tie, she sat on the butt strap and I had to slap her in the butt to get her to move up and then had someone hold her until I could undo the butt strap..  Although she usually doesn't give me much problem, this was the first time we'd been camping away just us.. no other horses in our "group". If i hadn't had help, it could have been a problem if she sat on that butt strap so hard it broke and she tumbled out....

How can I teach this mare to be more patient and mannerly in the trailer?...  We also had a little issue with her fretting on the trail while I had stopped her and was getting my glasses out of my waist pouch and trying to read the trail map... She wasn't real bad, but stepped around a bit wanting to get on down the trail..and I want her to stand STILL...  She is somewhat of an alpha mare.. Usually respectful, but occaisionally gets into my space ( ie: on my foot), especially if she's intent on something else going on. 

First, I'd start with ground work... back, stop, walk forward, stop, etc.  I used to practice backing down the aisle at my barn, coming and going.  Also had him back into his stall on occasion.  He learned to back when I said back, which really helps during trailering.   Once they back when you say back, and whoa when you say whoa, then try it in the trailer.  Work on loading and unloading and using "Loadup",  "back" and "whoa" as cues for your horse.  Practice loading and having the horse stop every step or so - it is really valuable if they every start to back and are still tied.  If they blast out, load up again and keep trying until you get some cooperation.  The first time the horse unloads nicely, quit.  Try it on a daily basis if you can.  I did this with my horse.  At first he would load, then I could not get him to back out!  The first day I spent quite a bit of time; I just loaded and unloaded until he got it right, then he got praised and we quit for the day.  One thing to avoid, don't load then immediately unload.  I did that and then the horse thought that was what he was supposed to do:(  I could not get him to stay in the trailer and had to work to get him to understood I wanted him to load and unload when I gave him the word, not when he was ready. 

Oh, and as for not tying in the trailer, I had a straightload and on the advice of someone else, did not tie.  I did that only once.  When I went to unload him (he was still young) he actually turned around in that little space before I could get the back doors open.  It bent the divider and butt bars so I could not get the butt bar off and let him out.  I had to get in there and kick the living daylights out of that thing to be able to unload him.  He ended up with a bloody nose, a few scrapes and a very sore back from turning himself around like a pretzle.  It sure made for a lot of noise and that trailer was a rockin!  He is a good boy now, but we sure had some scary moments.  I think trailering is the scariest thing I do with my horse.

I ended up buying a slant load so I would not have to deal with my horse unexpectedly backing out over the top of me.  He would not always do it but enough that I got a slant load.  It is safer for me now for sure, but I do make him still back out!!!  I rarely let him turn around and walk out forward, only because if I ever have to trailer in a straightload again, I don't want him thinking the only way to get out is to turn around.  My new 2 horse slantload with LQ has a rear tack, so he has to back out now unless we use the first stall. I walk in with him and we unload very slowly and carefully.  He is a good boy but is easily spooked so I try to keep unloading a very calm and methodical event.  Last September my truck broke down and I had to unload on I-90 in the blowing wind and rain on a mountain pass.  It was very scary for me thinking about everything that could go wrong, with semi trucks going by at 70 mph, rain and spray everywhere, but he was great... unloaded like a champ and loaded into a friend's trailer with no question.