Hi Equilove, my mare does the same thing. My trainer taught me that when she snakes her head, even if she's doing what I wanted, make her go faster. Of course she snakes more, and I make her go faster, then do a quick stop on the lunge and make her change directions. Of course for the first 15 minutes or so, she keeps it up. When I first start with her, I do hips over, back, cross front legs, and then flex her head around in the direction I am, and then do it all over on the other side. Then I send her out on the line. As far as I'm concerned she can walk if she wants to UNTIL she snakes her head and then we're off. You know my trainer blamed it on her being a mare too, but I recently read an article at myhorse.com where the guy writing it said that was bull. This country was built by horses, and mares and gelding, etc. worked side by side and they didn't have these 'marish' days. He said if a mare spooked in a trail it was because she was a mare, but if a gelding spooked it was because something really spooky happened and he couldn't understand where this thinking had started or come from. I thought about that article a lot, and I think it's because we don't give our horses 'jobs.' Now I haven't been able to ride in about 6 months. I get a ride to the barn twice a week, and VT had a horrible spring, it rained forever like other places before moving right into unbearable heat. I had a new saddle (for us) that I bought for $50.00 from the BO that was way too nice to sell for that but she insisted she had planned to put it on craigslist for that. I brought it home to clean and oil in between visits to the barn, and I made three visits after that before I could even try it on my mare. I hadn't put the stirrups back on and on the third visit I did that and had planned to try it on, but just getting them back on had me sweating in the shaded barn. The next visit was cooler and I put it on her and took her in her rope halter, and my old bridle because I want to work on her reining before I use the bosal I have, and when we got down there the herd came racing down to the outside of the arena, and she took off at a dead run, but at the end of the lunge turned it into a circle and continued to canter, was on the right lead, and not a snaking head in sight. I don't know if the herd distracted her or if being at a new barn with me being her only constant made her lose the attitude for then. But she did everything I asked.
I can honestly say that in the 3 years I've had her, it was the only time
Where she was before the same BO was there working with us both and saw her more often than I did. I didn't mean to run on I'm just wishing you a lot of luck with the speeding your mare up because doing it with mine didn't do a thing.
The reason I'm wanting to work on her reining is because I'm close to a gymkhana and want to start taking her and give her some WORK to do. Cheryl