Troping.

My horse tropes a lot. It is annoying and I want to get him out of the habit. He doesn't trope slowly, he does it really fast which is weird.

Is a trope one of those silly half trot half canter gaits?

Yes hehe. I don't' know where he picked it up from, he usually does it on his lazy days but now its more recurring. Its starting to make me hate loping him. :roll:

He's a lot like this horse when he does, Solomon is almost constantly doing it though, sometimes he won't but he generally does. http://www.youtube.com/watch?v=5BmXNTkrQGI

Get him on a lunge line and work him from the ground. Ask him to canter and when he does the trope take him straight back to a steady trot and ask again. Keep asking until he does it. He knows how to do it so he should get it

Unless he is doing it because he has something going on in his back or hips or something. Does he seem like he has any pain?

He doesn't swish his tail or refuse to canter. I don't ride with a saddle and I haven't for a good three or four weeks so it's not saddle pain. It may be left over pain, I'll check his back. He will pivot his hindquarters and forequarters with ease, back, side pass, walk and trot and all that as usual. This past week or so he has made it his gait of choice. The crappy thing is his trot stinks as it is, he's basically pacing when he trots and his canter is okay as long as we are in the arena but out on the trails, as we usually are, he gets excited and his canter gets sloppy, so together they're like a train wreck.

He trots like this horse does, he doesn't know what slow means.
http://www.youtube.com/watch?v=fH8KZVhKBLI

I have two otstd pacers. You think YOU've got problems with gaits??? HA! Got ya beat here! Anyway, my horses have had to learn how to not pace, period because it's just about impossible on the terrain here. It was pretty funny watching them try to pace and losing their balance! After some experimenting, I found that on even ground they can do just about any gait they want and be fine with it, but as soon as I take them off the road and into rough terrain they HAVE to drop the pace, even the "prot" as I call it doesn't work. They are not secure until they are in a complete trot or canter. Lots of uneven work and hills. Trotting and cantering up and down hills is lots easier than protting or troping! Also, deep heavy snow makes uneven gait difficult.

We have a lot of snow, as I live in Michigan. The roads are clear but anywhere with grass or trees still has anywhere from a few inches to a few feet with a bald spot here and there. His pasture is full of hills, valleys and creek/stream for him to jump, and wade through, which he does but still tropes. I cannot figure out how to get him out of the habit, he will trope EXTREMELY quickly and will never break fully into the canter, if I keep pushing him, he will try to gallop and then trope again or he'll balk since he is not confident in the gallop yet.

If he's pacing you can do some trot pole work with him. He should learn to trot over the poles because he wont be able to pace over them ;) I've been dong this with my 25 year old stb cougar with some success. He is trotting more now but still paces a lot of the time as well. But he's definitely trotting more than he was before trot pole work. That's also how I jump him now. He used to pace around all the time so jumping was next to impossible but with trot poles leading up to a jump he is fine.

Also do you rise or sit the trot? Although its tough to do when they are pacing, rising can often force them to trot. I don't know the theory behind this but that has also been helping with cougar.

I usually rise the trot.

I think that this "troping" is just a 4-beat canter, which is very hard to train out - push him forwards into a FORWARD canter, don't let him slow down into a 4-beat. Eventually you can collect up again, but you need to keep the energy coming from behind.