Which of the following is NOT listed as a wood defect?

• A. Knots
• B. Milling
• C. Pitch pockets
• D. Cross grain

Answer: (B)

Defects in lumber are flaws that affect its strength, workability, or appearance. Knots are a common defect because a branch remains embedded in the wood, creating weak points and irregular grain. Pitch pockets are resin-filled areas that can interfere with finishing and can weaken the surface. Cross grain occurs when the wood’s grain runs at an angle to the length, which can cause tearing, warping, or reduced strength when cut or shaped. Milling, by contrast, is the process of cutting and surfacing wood to its final dimensions and finish. It’s a manufacturing operation, not a flaw inherent to the wood itself. While improper milling can introduce surface imperfections, those are processing issues rather than wood defects. So milling is not listed as a wood defect.