07/07/2026
Doesn't even look like the same horse, right?
Coloring aside, this is because horses are not skeletally mature until at least 5.5 years old. This applies to smaller in stature mares - switch to a male, add in more height and a longer neck and it will be closer to 8 years old before all growth plates are fused.
The last fusion to occur happens in the spine and the lower neck - this is why we need to be so careful about how we develop our young horses. We are sitting directly on this fragile area and (hopefully) asking them to lift the base of their neck as part of the recipe of self-carriage. We must respect the instability in these areas the first handful of years if we expect to keep them sound long term.
I will always advocate for slower starts! There is no horse on the planet that has matured 'early' - it is physically impossible. Some breeds, like the QH, have been bred to appear more mature at a younger age. This doesn't mean their skeletons are.
(Also, if you know me at all, you know that my young horse didn't just sit at home for the last 4 years. There are appropriate ways to work with youngsters to help build strength while at the same time making your job of actually starting them under saddle easy as pie 💁♀️)
a good article worth a read if you haven't already from Dr. Bennett ⬇
https://www.hoofrehab.com/ArticlesPDF/Timing%20and%20Rate%20of%20skeletal%20maturation%20in%20Horses.pdfTiming%20and%20Rate%20of%20skeletal%20maturation%20in%20Horses.pdf
