How do you evaluate a horse's scope over a fence?

Evaluating a horse's scope — its natural physical ability to clear fences significantly larger than what it is currently jumping — requires observing specific qualities in the horse's jumping effort rather than simply noting whether it cleared the current fence, because a horse that barely clears small fences and one that leaps them with obvious reserves may both be jumping the same height but have very different scope ceilings. The most reliable scope indicators are visible in the quality of the jumping arc and the degree of physical effort the horse shows at the current fence height. A horse with genuine scope will jump smaller fences with a generous, floating arc that carries the body well above the fence — not just clearing it by inches but clearing it by a comfortable margin with an arc that suggests the horse could jump significantly more height without changing its approach. The front end technique at the current height also predicts scope ceiling: a horse that already shows maximum front end effort at a small fence — front legs working at maximum tuck, knees approaching the chin, obvious physical strain — is suggesting that its scope ceiling may be relatively low, while one that jumps with loose, casual front end technique at the same height has physical reserves that better scope suggests. Watching the horse jump increasingly larger fences during a trial is the most direct way to assess scope: raising the fence and observing whether the horse's technique and arc remain comfortable as height increases, or whether the horse begins to show signs of maximum effort at a specific height, reveals the approximate scope ceiling. The horse's hind end over larger fences also reveals scope: a horse that consistently clears large fences cleanly behind, with active hind leg use that keeps the hind feet away from the rails, has better overall scope than one that regularly taps or takes down rails with its hind legs when approaching its physical limit.