The "Cross Country Obstacle Design Guidelines", avaliable on the USEA web site, says
-Training - Greater than 11’ height and of minimal impact
-Preliminary/Advanced – 11’ minimum from ground to
bottom of roof top or frame.
“Hole” should not be less than 6’ x 6’. Never to be used in association with water. Jump materials should be of light color in situations where shadows come into play. Where roof takes “effect”, i.e. has great effect on the horse, top spread should not be more than 50% of height permitted.
It also has "minimum width of face" for each level.
chief feeder and mucker for Music, Spy, Belle and Tiara. Someone else is now feeding and mucking for Chief and Brain (both foxhunting now).