Bitting rig rig." It is the use of additional reins such as the overcheck, or the use of leverage to place the horse's head in a set position that turns a classic surcingle into a bitting rig. Both a bitting rig and a classic surcingle with side reins are intended only to be used while longeing a horse. They are not to be used on a horse that is standing in a stall (though this is a very common type of misuse), nor are they used while riding. However, the surcingle and side reins are used as safety tools in the sport
Tree girth measurement noted below, in addition to basic girth measurements. A variety of monocular w/reticles are available from different manufacturers. They can be used as hand held instruments but more accurate reading can be obtained when mounted on a tripod. Some higher end electronic surveying devices, like the Criterion RD 1000 have an electronic version of the reticle scale built into the device and can be used to measure diameters. Photographs of trees can be used to determine girth or other measurements if there is a something of known size in the photo to provide a scale. The following information must be