Wood Handbook, Wood as an Engineering Material

Redwood

Redwood (Sequoia sem‑

pervirens) grows on the

coast of California and

some trees are among

the tallest in the world.

A closely related species,

giant sequoia (Sequoia‑

dendron giganteum), is

volumetrically larger and

grows in a limited area in the Sierra Nevadas of California,

but its wood is used in very limited quantities. Other names

for redwood are coast redwood, California redwood, and

sequoia. Production of redwood lumber is limited to Cali-

fornia, but the market is nationwide.

The heartwood of redwood varies from light “cherry” red

to dark mahogany. The narrow sapwood is almost white.

Typical old-growth redwood is moderately lightweight,

moderately strong and stiff, and moderately hard. The wood

is easy to work, generally straight grained, and shrinks

and swells comparatively little. The heartwood from old-

growth trees has high decay resistance; heartwood from

second-growth trees generally has low to moderate decay

resistance.

Most redwood lumber is used for building. It is remanu-

factured extensively into siding, sashes, doors, blinds,

millwork, casket stock, and containers. Because of its dura-

bility, redwood is useful for cooling towers, decking, tanks,

silos, wood-stave pipe, and outdoor furniture. It is used in

agriculture for buildings and equipment. Its use as timbers

and large dimension in bridges and trestles is relatively mi-

nor. Redwood splits readily and plays an important role in

the manufacture of split products, such as posts and fence

material. Some redwood veneer is produced for decorative

plywood.

Spruce, Eastern

The term eastern spruce

includes three species: red

(Picea rubens), white (P.

glauca), and black

(P. mariana). White

and black spruce grow

principally in the

Great Lake States and

New England, and

red spruce grows in New England and the Appalachian

Mountains.

The wood is light in color, and there is little difference be-

tween heartwood and sapwood. All three species have about

the same properties, and they are not distinguished from

each other in commerce. The wood dries easily and is stable

after drying, is moderately lightweight and easily worked,

has moderate shrinkage, and is moderately strong, stiff,

tough, and hard.

The greatest use of eastern spruce is for pulpwood. Eastern

spruce lumber is used for framing material, general mill-

work, boxes and crates, and piano sounding boards.

Spruce, Engelmann

Engelmann spruce (Pi‑

cea engelmannii) grows

at high elevations in the

Rocky Mountain region

of the United States. This

species is also known as

white spruce, mountain

spruce, Arizona spruce,

silver spruce, and balsam.

About two-thirds of the lumber is produced in the southern

Rocky Mountain States and most of the remainder in the

northern Rocky Mountain States and Oregon.

The heartwood of Engelmann spruce is nearly white, with

a slight tinge of red. The sapwood varies from 2 to 5 cm

(1 to 2 in.) in width and is often difficult to distinguish from

the heartwood. The wood has medium to fine texture and is

without characteristic odor. Engelmann spruce is rated as

lightweight, and it is low in strength as a beam or post. It is

also soft and low in stiffness, shock resistance, and shrink-

age. The lumber typically contains many small knots.

Engelmann spruce is used principally for lumber and for

mine timbers, railroad crossties, and poles. It is used also

in building construction in the form of dimension lumber,

flooring, and sheathing. It has excellent properties for pulp

and papermaking.

Spruce, Sitka

Sitka spruce (Picea

sitchensis) is a large

tree that grows along

the northwestern coast

of North America from

California to Alaska. It

is also known as yellow,

tideland, western, silver,

and west coast spruce.

Much Sitka spruce timber is grown in Alaska, but most logs

are sawn into cants for export to Pacific Rim countries. Ma-

terial for U.S. consumption is produced primarily in Wash-

ington and Oregon.

The heartwood of Sitka spruce is a light pinkish brown.

The sapwood is creamy white and shades gradually into the

heartwood; the sapwood may be 7 to 15 cm (3 to 6 in.) wide

or even wider in young trees. The wood has a comparative-

ly fine, uniform texture, generally straight grain, and no

Chapter 2 Characteristics and Availability of Commercially Important Woods