Types of Wood

COLOR

A tree contains both heartwood and sapwood. The heartwood extends from the center of the tree to the edge of the sapwood. This portion of the tree no longer contains living cells. It is usually filled with resins, gums or other materials (e.g. tyloses) that contribute to the coloring. When we mention the color of a wood, we are almost always speaking of the color of the heartwood.

The sapwood is found near the outside of the trunk and branches of the tree. This layer contains living cells. Its principal function is the storage of food and the conduction of sap. It should not be confused with the cambrium layer. The cambrium layer is located between the sapwood and the bark, and its cells are continually subdividing to produce new layers of both bark and wood. Almost all sapwoods are light in color or virtually white. Any coloring is usually due to a discoloration from fungus or chemical stains.

GRAIN, TEXTURE, AND FIGURE

Grain texture, and figure are all terms describing the surface appearance of the wood. Unfortunately, they are used rather loosely and tend to overlap on meaning. This produces a certain amount of confusion. Grain is often used in reference to the fibers of the wood, their arrangement, their prominence, the direction in which they run, or to the annual growth rings and the spacing between them.