Does my horse have an ewe neck? 

If he does its very slight, can't really tell from this angle

 Will her having an ewe neck be a problem?

 It's hard to tell from this picture, but I don't think she has a "true" ewe neck.  With an ewe neck, both the upper and lower sides of the neck arch downward and the neck is set on rather low, below the point of the shoulder.  This can cause the horse to be high-headed, which correlates into a problem with bit contact and control.

What is does look like she has is more than a desirable amount of muscling on the underside of her neck, but without the downward arch on the upper side. 

 Could that muscle be because she weaves a lot? How do I get the muscle in the top?

 It is hard to tell from that pic, but if she does, it is only very slight.  Working long and low with her on the flat will help build her topline, along with longeing in side reins, to build the correct muscles along the topside of her neck and balance it out.  It also looks like your bit is sitting a bit too low in her mouth.  I would raise it a hole on your bridle so it is not just hanging there and possibly hitting her teeth.

 I will work with her on the lunge with side reins.

I will raise it up when I go to ride again. I am actually thinking of using a hackamore. I ride her with a bit and she listens but not that great. i ride her with just a halter and leads and she's perfect. But like you said it could be because the bit is too low. We'll see what happens when I raise it up a hole.  Thanks

Dukey, I agree with Solaris that it's hard to tell from that angle, but I'm not seeing it myself.  Measure the top and bottom lines of her neck.  If they're pretty much equal and she's high-withered, then, yes, she's ewe-necked.  You want the top line to be double the bottom for the best chance of flexion.  If the bottom line of her neck is too long, you won't be able to work her long-and-low because she won't be physically able to lower her head sufficiently to do that.  If her measurements are good, then Solaris is right.  Work her with her head low and ask for flexion at the poll to build the top muscles.

But my QH mare never did build significant crest muscle.  She just wasn't genetically programmed for it.  There's only so much we can do to fight genetics.    You can minimize the over-building of lower neck muscles by not allowing her to fight against your hands.  A horse constantly fighting to keep you out of her mouth will build wonderful muscles along the lower side of her neck, believe me!

 Thanks for the tip. I'll go measure her tomorrow and let you know.

Dukey - your horse lacks topline - a muscle under the neck is the result of resistance from your horse and holding the head high thus hollowing out!

To build up the topline you need to work the muscles over the back - think of it like an elastic band that stretches from the ears to the top of the tail - at the moment it is tight and short you want supple and elongated and this can be achieved by working long and low - plenty of lunging - hill work - you need to get your horses power unit working ie working from the hocks forward instead of her working on the forehand - if there is a resistance to the bit maybe a hackamore will help, as it sounds like she is more relaxed with no one hanging off her mouth - from the picture too it looks like she is a little dippy in the back with a high wither - just further confirmation that she is lacking topline.

Thanks for the tip. It helps getting other peoples opinions. I do have a hill that I can work on with her. I do have a problem lunnging her. She doesn't respect me on the lunge line. She is a hot horse and likes to pull the line out of my hands and take off. That's something I'm still trying to work with her on.  The only place I have to lunge her is a square 50x50 paddock, which is hard for her to canter in because it's so tight, or an acre fenced in field where she takes off on me.  But i have been working with her on it and she is starting to get better, but she has her "mare" moments. Thanks. 

She doesn't really have a ewe neak, just no top line. Try some dressage work, like lifting her back and reahing for the contact. She will have a hard time at first, but she will improve. Her bit is low. There is a lot of muscles on the bottom of the neck necause she pulls against you, so try to teach her to work with her head lower. She is really cute!

Lunging or riding her with side reins will help. But when you start her in them, they should be fairly loose. Just enough to keep her face paralell to the ground. Work for short periods of time to start. Its the same as when you start to work muscles that you aren't used to working, They are going to burn and be sore the next day. Start offf slowly. If you use them wrong they can really damage your horse. I prefer a running martingale. It allows the horse to come up but encourages them to stay down.

I know this post is older, but I just wanted to warn you about over using side reins. 

I think that a 'ewe neck' is actually much more pronounced. I think what your horse has is an 'upside down neck'.It can be made much better.  When I first started working with Tar Baby his neck was UGLY Have you seen pictures of burros? That was I had to start with. now he looks like a different horse.

 Thanks guys for your input. I guess I need to get a pair of side reins.

Dressagerider3, I have seen pics of burros. They do kinda have an ugly neck. I would love to see Tar Baby's neck now. You have any pics?