Woods to Know: Redwood

Woods to Know: Redwood

Redwood (Sequoia sempervirens)

Situated in northern coastal California is a magnificent forest, home to the tallest and largest trees in the world: the California Redwood (aka Sequoia, Coast Redwood, or California Redwood). They are an ancient group – Redwood fossils are known as far back as the Jurassic period. Acclaimed author John Steinbeck referred to them as "ambassadors from another time."
 
The trees are giants – heights of over 350 feet are common and widths can exceed 25 feet. Branches can exceed 5 feet in diameter and the bark itself is over 12 inches thick. Several factors can account for these outstanding dimensions. They are long-lived trees with ages over 2,000 years, allowing plenty of time for growth. The dense bark protects them from forest fires and insects. In fact, this tree is fire dependant. Forest fires will leave the Redwoods untouched while removing competing trees.
 
The heartwood is a distinctive pinkish brown aging to deep reddish brown. The sapwood is a pale white to pale yellow. It is straight grained with a coarse texture. Redwood can exhibit curly figure and it also produces burls, some of them quite massive. The heartwood is rich in tannins making it an extremely durable wood. For a softwood, it has a surprisingly low resin content, giving it fire resistant properties. Growth rings in old growth material are very dense. This increases the strength of this lightweight wood. 

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The wood has been used for veneer, trim, millwork, general construction and decking. It was outstanding for all exterior uses, especially siding. Redwood continues to be used in fine musical instruments and the curly and burl figures yield all manner of decorative objects.
 
Redwood will dry with little degrade and it is very stable once dried. These massive trees produce lumber with large dimensions and with few knots. The wood is easy to machine and works well by hand. Figured wood may tear; so slower feed rates and lower blade angles work best. It glues and takes fasteners well. It will accept all finishes and is especially amenable to staining. It handles exterior paints with ease and can be used unfinished as well.
 
A wood possessing many beneficial characteristics leaves itself open to exploitation and this is true of the Californian Redwood. Old growth forests have been reduced to just 4% of their original range. Most of the Redwood now on the market is secondary growth, and there is considerable debate about its performance compared to the older trees. The second-generation trees are harvested younger, so the resulting lumber will have more knots, sapwood and fewer growth rings. Since it can take over 90 years before the heart starts developing its weathering abilities, younger trees may be less durable.

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The woodworker has to take all of these factors into consideration when purchasing Redwood. First-growth Redwood is available as reclaimed material or salvaged logs. It is considered an endangered species due to over cutting, fire suppression and habitat destruction. It can be purchased from certified responsible dealers from other countries where it can thrive as an introduced species.
 
Redwood is a unique historical wood that woodworkers and craftsmen should explore. Used responsibly, it will continue to have a place in the shops of tomorrow. You can also show your support and respect for this magnificent tree by seeing it in its natural habitat. Few people come away not impressed by its majestic beauty.
 
 
Average Dried Weight26 lbs/ft³A measure of its weight at 12% moisture and an ambient temperature of 70°F.
Specific Gravity.42A measure of the ratio of its density compared to water (at 12% MC)
ShrinkageRadial: 2.4
Tangential: 4.7
Volumetric: 6.9
Radial (the amount of crosswise shrinkage);
Tangential (the amount of lengthwise shrinkage);
Volumetric (the total amount of shrinkage.)
T/R Ratio2.0A measure of the uniformity of tangential to radial shrinkage.
Janka Hardness450 lbfA measure of resistance to denting and abrasion.
Crushing Strength5,690 lbf/in²A measure of compression strength parallel to the grain.
Colour
Heartwood is a pinkish to deep reddish brown. Sapwood is a pale yellow to white.
GrainStraight grained. Curly and burl figure can be present. Old growth trees have dense growth rings.
TextureCoarse.
Workability
Works well by hand and machine. Glues and accepts fasteners with few problems. Works with all finishes. 
UsesMillwork, general construction, decking, musical instruments, furniture.
Price$7.00/lf 2"x6" deck board
Clear and/or figured woodworking lumber is likely to be much more expensive.
 
  
Photos and Specifications Courtesy of: The Wood Database