Surcingle behind the withers. When used with a saddle, the surcingle runs over the seat near the pommel. A surcingle is also used over the top of certain types of pack saddle and pack to keep the pack bags and swag in place. A surcingle is usually used with a pad, and fit to the horse's back as carefully as a saddle would be. It is tightened enough to prevent slipping, more when used with a saddle and rider, less when used for ground training. Surcingle A surcingle is a strap made of leather or leather-like synthetic materials such as nylon
Tree girth measurement is measured at a height of , , or . The base of the tree is measured for both height and girth as being the elevation at which the pith of the tree intersects the ground surface beneath, or where the acorn sprouted. On a slope this is considered as halfway between the ground level at the upper and lower sides of the tree. This "breast height" value is a measurement grandfathered from decades of forestry applications. It was developed because of the simplicity and ease of measurement. There is no one ideal height at which to measure girth. Tree