Now, I don't know anything about working cattle on a horse other than you point the horse toward a cow and the cow runs. And for now, I don't have any interest. Tanner seems to have other ideas. If I asked for anything past a walk, and had her pointed in even the general direction of a cow, she'd haul off after it. She'd let me pull her back if I asked, and wasn't getting out of control or anything, but she did startle a few cows and send them running. (We have pretty gentle cattle, for the most part, and they're not real excitable.) The whole herd was pretty relaxed about us, and just kinda lazed all over on all sides of us, so it's a bit hard to avoid them.
Her previous owners told me that she'd been used to work cattle, but didn't go into detail, and I didn't really ask. So, presumably, she knows how to work cattle and is just working off some kind of cue that I'm giving her without realizing.
At any rate, for future reference, what might be a cue that would tip her off to take after a cow? I'm almost 95% sure it's something I'm doing without realizing it, I just don't know where to look to help cut down on the cow chasing.
(It's not really something I want to break her of, though; I eventually want to try my hand at cattle work. But right now, I have too many horse-projects started to pick out a new one. )