The group of trees commonly referred to as “cedar” has been widely used throughout history, valued for its unique combination of aesthetic and functional qualities. This versatility stems from specific chemical and physical characteristics that make the wood naturally resistant to decay and insect damage. The term “cedar,” however, is applied to several different genera of trees, meaning the specific properties and uses vary significantly depending on the species. These properties, including notable longevity and distinct aromatic profiles, have cemented cedar’s place in applications ranging from heavy construction to fine perfumery.
Understanding the Different Types of Cedar
The common name “cedar” is applied broadly to trees from several botanical genera, leading to variation in their properties and uses. True cedars belong to the genus Cedrus, encompassing species like the Atlas Cedar, which are primarily valued for their ornamental appeal.
Most commercially important woods called cedar, however, come from the Cypress family (Cupressaceae). This group includes Western Red Cedar (Thuja plicata) and Eastern Red Cedar (Juniperus virginiana). Western Red Cedar is known for its dimensional stability and natural decay resistance, making it suitable for exterior construction. Eastern Red Cedar, which is technically a juniper, possesses a high concentration of aromatic oils, dictating its use in specialized applications.
Primary Uses of Cedar Wood in Construction
Cedar wood, particularly Western Red Cedar, is highly valued in exterior construction due to its inherent resistance to decay and insect damage. This durability comes from naturally occurring fungicidal compounds, such as thujaplicins, which permeate the wood structure. These extractives protect the material from fungal growth and wood-boring insects, significantly extending the service life of outdoor structures.
The low density and straight grain of many cedar varieties contribute to excellent dimensional stability, meaning the wood resists warping, swelling, and shrinking when exposed to moisture changes. These traits make it an ideal material for applications that frequently encounter weather, such as exterior siding, deck planking, and fencing. The wood also accepts a wide range of finishes, including oils, stains, and paints, allowing for aesthetic customization.
Cedar is also used for roofing, often cut into durable shingles and shakes that offer superior insulation due to air pockets within the wood structure. In maritime applications, cedar’s natural resistance to moisture uptake has historically made it a choice material for small boat construction, particularly for strip-planked canoes and kayaks.
A specialized indoor use is the construction of humidors, where Spanish Cedar (Cedrela odorata), which is not a true cedar, is preferred. This wood maintains a stable, high-humidity environment due to its porous structure and ability to absorb and slowly release moisture. The aromatic oils in Spanish Cedar are believed to deter tobacco beetles while enhancing the flavor profile of stored cigars.
Aromatic Applications and Essential Oils
The distinct aroma of cedar stems from volatile organic compounds (VOCs) stored within the wood’s heartwood, particularly in species like Eastern Red Cedar (Juniperus virginiana). These natural compounds, including cedrol, function as effective insect repellents. This makes the wood highly sought after for lining clothes closets and crafting traditional cedar chests to protect wool and natural fibers from moth damage.
Beyond direct wood use, these aromatic compounds are extracted through steam distillation to produce cedarwood essential oil. The oil’s composition, rich in sesquiterpenes, provides fixative properties highly valued in the fragrance industry for stabilizing and extending perfume longevity. Different cedar species yield oils with varying scent profiles, from woody and dry to sweet and balsamic, making it a foundational element in many fragrance formulations.
In aromatherapy, cedarwood oil is frequently used for its calming and grounding effects, often incorporated into diffusers and massage blends. The primary active component, cedrol, contributes to the oil’s use in promoting relaxation by interacting with the olfactory system. The absorbent nature of cedar shavings also makes it a common choice for animal bedding, where it helps to neutralize odors and absorb moisture.
Horticultural and Ecological Roles
In horticulture, cedar species are widely planted for their aesthetic appeal, often serving as ornamental trees in landscapes and public parks. Their dense, evergreen foliage makes them excellent choices for creating year-round privacy screens and hedges. Many species are also tolerant of urban pollution and poor soil conditions, adding to their utility in managed environments.
Ecologically, cedar trees provide several important functions in natural and agricultural settings. Their extensive root systems stabilize soil on slopes and stream banks, mitigating erosion and managing runoff. Cedar stands also serve as winter cover and nesting habitat for various bird species and provide browse for deer and other mammals.