My yearling (horse) bites and kicks!?

Your yearling sounds exactly like mine did. He is a rescue and had very bad manners. It was to the point that we could not even go into the pasture. One time he reared up and came down on my husbands shoulders and nearly killed him. In January one of my horses coliced. When the vet came out to see him, Rocket was up to his old trick. He was really showing out. So when he took my colicky horse to his hospital, I sent Rocket along too thinking that gelding him would do the trick. WRONG! So I went to my local coop and ask this lady that worked there if she knew of someone who could take him and teach him some manners that wouldn't break me. That afternoon a young man called and told me that not only was he a trainer, but also a farrier. Rocket's feet looked horrible and he refused to stand for the farrier. So I let this young man take him to his farm for three weeks. He worked with him every day and when he brought him home, I thought it was someone else's horse. He is now very calm, stands for the farrier, no longer bites or kicks. I have had a life-long affiliation with horses, but to this day I don't know how to get them to behave, at least with situations such as this one. I strongly suggest you find someoone who has experience with yearlings and send him for some lessons in good manners. Believe me, you will never be sorry for doing this, you will be very thankful. Best Of luck to you