a graduated rule for measuring the small-end diameters of logs under bark and estimating the board-foot volume or heights of trees or logs —note 1. the scale stick is usually marked in 1-in (2.54 cm) diameter classes to 40 in (101.6 cm) DBH, tree heights up to five 16-ft (4.87 m) logs, and board-foot volumes for various log lengths and common log scales —note 2. a log rule is generally reproduced on it (log scale) so that lumber contents can be read off directly (log scale) —note 3. a stick fitted with calipers and graduated for the volumes of logs of different lengths is a caliper scale —synonym scaling stick —see lumber rule This definition last updated 08/02/2008