Hardwoods are graded by the National Hardwood Lumber Association. Here's a chart to help explain the grading system. Grades are listed from highest to lowest. Grades of Softwoods Softwoods are divided into dimensional lumber, with a grade based on strength, and appearance boards, which are typically used for woodworking projects. Grading of softwoods is overseen by a number of different agencies, so you will be more likely to find some variations in terminology.
Grades listed here are from highest to lowest.
What It Means C Select Almost completely clear of defects. Widely used for interior trim and cabinets. D Select Fine appearance, similar to C Select. May have dime-sized knots. 1 Common Best material for high quality pine with a knotty look.