This article, written by DNR forest products team leader Collin Buntrock (contact him in Rhinelander at 608-286-9083) and DNR forest products specialist Scott Lyon (contact him in Green Bay at 920-360-3722), discusses log scaling and explains what separates the three commonly-used methods of scaling hardwood logs in the U.S.  It also explores common defects and provides the accompanying formulas for calculating appropriate deductions for each defect: https://p.widencdn.net/wfabyu/Hardwood-log-scaling