What are pin knots in walnut trees?

What are pin knots in walnut trees?

• A. Natural resin pockets.
• B. Defects resulting from suppressed dormant buds that may not break through the bark.
• C. Sunburn damage.
• D. Insect hole galleries.

Answer: (B)

Pin knots are small defects in walnut wood created when dormant buds on the tree are suppressed and never sprout through the bark. Those latent buds remain under the surface, and as the tree grows, the surrounding wood forms around the hidden bud, revealing a tiny knot when the log is milled. This can disrupt grain and reduce lumber quality or finish. The other options describe different phenomena—resin pockets occur in some softwoods, sunburn damages the bark rather than internal wood, and insect Galleries are caused by wood-boring insects.

Pin knots are small defects in walnut wood created when dormant buds on the tree are suppressed and never sprout through the bark. Those latent buds remain under the surface, and as the tree grows, the surrounding wood forms around the hidden bud, revealing a tiny knot when the log is milled. This can disrupt grain and reduce lumber quality or finish. The other options describe different phenomena—resin pockets occur in some softwoods, sunburn damages the bark rather than internal wood, and insect Galleries are caused by wood-boring insects.