Jumping on the Trail and "Moar" English Words Dude Knows

I did it! I cleaned Dude's sheath yesterday. He did not mind. We will NOT discuss the look on his face... We also found out on the trail yesterday, that he fully understands the meaning and implications of the word "SNAKE!!" When I yelled it out he did the best halt ever. We jumped ditches and cantered a little and he didn't go too nuts, but he wanted to run. I'm comfortable now letting the reins way out so he's not shaking his head at all after jumps. He wears a hackamore, anyway, but I'm sure it smarts if it gets jerked. I want to take him to the arena so I can let him run without my worrying about him running all the way home. Its my fear that's the problem, now. I tell myself I'm doing a lot of trotting work that is the foundation. It really is, and when I'm ready to canter more I will be ready. My trotting is getting much better. I watch my shadow along the trail and check my posture.