Great article on starting young horses

[schwung]

This is an excellent article from the Equine Studies Institute on starting young horses. The basic idea of this is, no matter what the breed, NO horse is physically mature until age 6. She doesn't specifically say a horse should not be ridden until 6, but does give specifics about what is going on in the various growth plates throughout development, and what risks you take by starting your horse in demanding work early.

www.equinestudies.org/knowledge_base/ranger.html