Most people say that horses don't need their hooves trimmed in the winter time.People that beleive that have been misinformed.Because Horses need their hooves trimmed every 6 to 8 weeks.Or they will start to break off and become off balance.In the winter months it is true that they don't grow as fast and also the sole of the foot grows with the hoof wall to protect the foot.So in the warmer months horses are moving around alot more.So their feet are expanding and contracting and that motion is what makes the hoof wall grow.So in the winter horses don't move around alot so there is very limited expanding and contraction.Along with the sole growing with the hoof wall it would appear that the hoof is not grow at all. It is real good that some people shoe their horses during the winter. Because it really raises the foot off the ground and protects the foot against the frozen hard ground.Where they could get stone bruizes,That can become abscessed