Wood Handbook, Wood as an Engineering Material

CHAPTER 2

Characteristics and Availability of Commercially

Important Woods

Michael C. Wiemann, Research Botanist

Throughout history, the unique characteristics and abun-

dance of wood have made it a natural material for homes

and other structures, furniture, tools, vehicles, and decora-

tive objects. Today, for the same reasons, wood is prized for

a multitude of uses.

All wood is composed of cellulose, lignin, hemicelluloses,

and minor amounts (usually less than 10%) of extraneous

materials contained in a cellular structure. Variations in the

characteristics and proportions of these components and

differences in cellular structure make woods heavy or light,

stiff or flexible, and hard or soft. The properties of a single

species are relatively constant within limits; therefore, selec-

tion of wood by species alone may sometimes be adequate.

However, to use wood to its best advantage and most effec-

tively in engineering applications, specific characteristics or

physical properties must be considered.

Historically, some species filled many purposes, whereas

other less available or less desirable species served only

one or two needs. For example, because white oak is tough,

strong, and durable, it was highly prized for shipbuilding,

bridges, cooperage, barn timbers, farm implements, railroad

crossties, fence posts, and flooring. Woods such as black

walnut and cherry were used primarily for furniture and

cabinets. Hickory was manufactured into tough, hard, and

resilient striking-tool handles, and black locust was prized

for barn timbers. It was commonly accepted that wood from

trees grown in certain locations under certain conditions was

stronger, more durable, more easily worked with tools, or

finer grained than wood from trees in other locations. Mod-

ern research on wood has substantiated that location and

growth conditions do significantly affect wood properties.

This chapter presents brief descriptions of many species;

current and, in many cases, historic uses are cited to illus-

trate the utility of the wood.

Gradual reductions in use of old-growth forests in the

United States have reduced the supply of large clear logs for

lumber and veneer. However, the importance of high-quality

logs has diminished as new concepts of wood use have been

introduced. Second-growth wood, the remaining old-growth

forests, and imports continue to fill the needs for wood in

the quality required. Wood is as valuable an engineering

material as ever, and in many cases, technological advances

have made it even more useful.

Inherent factors that keep wood in the forefront of raw

materials are many and varied, but a chief attribute is its

Contents

Timber Resources and Uses 2–

Hardwoods and Softwoods 2–

Commercial Sources of Wood Products 2–

Use Classes and Trends 2–

Species Descriptions 2–

U.S. Hardwoods 2–

U.S. Softwoods 2– 11

Imported Woods 2–

Imported Hardwoods 2–

Imported Softwoods 2–

Scientific Name Index 2–

U.S. Wood Species—Hardwoods 2–

U.S. Wood Species—Softwoods 2–

Imported Woods—Hardwoods 2–

Imported Woods—Softwoods 2–

Literature Cited 3–

Additional References 2–