Girth (tack) slightly too small, a girth extender may be used. A girth extender attaches to the billets of the saddle and lengthens them, so that a shorter girth may be used. Most jumping saddles have three billets. This not only allows the rider a spare should one break, but can also provide an adjustment option. For horses on which the saddle sits nicely, neither slipping forward or back, the first and third billets should be used. On horses where the saddle slips back, the first and second billets should be used. The second and third should never be used together, as
Tree girth measurement was repeated at different heights to create a three-dimensional model of the tree. This mapping process can be automated. Taylor has been developing a cloud mapping process using optical parallax scanning technology whereby thousands of measurements are made around the trunk of a tree. These can be used to recreate a three-dimensional model of the trunk and girth and diameter data are among the values that can be calculated. For long term monitoring of girth, the exact point on the tree needs to be marked to assure the measurement is taken in the same place every session. Forestry data suggests