Six Common Grain Patterns of North American Black Walnut

1. ● Teardrop Grain
This grain pattern is found on the tangential cut surface, where the center of the wavy pattern forms a teardrop-like pattern. Small teardrop patterns are usually accompanied by superimposed large mountain patterns, while large teardrop patterns are generally accompanied by wavy patterns.
2. ● Wavy Grain
This grain pattern is found on the tangential cut surface, perpendicular to the rays and parallel to the annual rings, producing a wavy pattern. The center of the wavy pattern is a teardrop pattern. The greater the distance between the wavy grain lines, the looser the wood texture. This is one of the most beautiful grain patterns of North American black walnut.
3. ● Straight Grain
This grain pattern is found on the radial cut surface, formed in the secondary xylem near the sapwood of the tangential cut surface. It is the most common and widely used grain pattern in furniture.
4. ● Mountain Grain
This grain pattern forms beautiful large parabolic patterns on the tangential cut surface. Mountain grain has only one peak, with peaks superimposed on each other, transitioning from mountain grain to wavy grain, and often accompanied by straight grain on both sides. The denser the wood grain lines, the higher the hardness and the better the quality.
5. ● Bird's Eye Grain
As the name suggests, this is a texture defect caused by bird pecking or other external factors. Sometimes it is contained within the inner bark, and usually refers to knots or blemishes. It has a complete grain connection with the surrounding structure, without forming a fracture, and without a pith structure.
6. ● Burl Grain
Burl grain is the cut surface pattern of a burl in black walnut wood. It is the tree's reaction to external injuries, such as insect infestation or damage caused by impact. It can have a variety of different patterns, constantly changing, and is the most delicate, hardest, and most dazzling grain pattern. It is often used in luxury goods decoration.