Well, last night the barn manager came out to the pasture with me when I brought them in. She took the dominant mare and stood aside with her and I took the one I'm having trouble with. I told her that I doubt she'll act up since she can see the other mare standing right there, and I was correct. She was a perfect angel heading into the barn.
So now I know that if they are brought in together everything is fine. The trouble is, when I bring in the horses, it's usually just me out there - there's no one else to help me. So.... I'm back to square one.
We'll see how she does tonight, I guess... But I think you're all correct - she is buddy sour. Any additional thoughts as to how to make the situation safer for me would be much appreciated. Thank you all for your comments!
Oh, and regarding the use of a stud chain... I've never used one, so I think I'll see how things go and if she's still acting up as violently, I'll ask the barn manager about using one and if she will show me how to use it correctly. (Do people have strong opinions about stud chains? I thought someone had told me before that they could break a horse's nose... which I think sounds a little outlandish, but I don't have any experience with one.)
Last edited by Rockey; 03-31-2011 at 10:35 AM.