Horses in warfare of today's English saddle. Both the Scythians and Assyrians used pads with added felt attached with a surcingle or girth around the horse's barrel for increased security and comfort. Xenophon mentioned the use of a padded cloth on cavalry mounts as early as the 4th century BC. The saddle with a solid framework, or "tree", provided a bearing surface to protect the horse from the weight of the rider, but was not widespread until the 2nd century AD. However, it made a critical difference, as horses could carry more weight when distributed across a solid saddle tree. A solid tree,
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