a modification of the international log rule based on 4 ft (1.2 m) log sections; the formula is V = (0.2D² – 0.71D) 0.905, where V = board-foot volume and D = diameter inside bark at the small end in inches, that uses a 1/8-in (0.32 cm) kerf —note also known as the international 1/4-inch rule, it is probably the most accurate rule and is used primarily with small-diameter logs —see Doyle rule, log rule, Scribner ruleThis definition last updated 07/17/2008