Red cedar is a common name applied to several distinct species of trees highly valued for their color, aroma, and durability. This name often causes confusion because these trees are not botanically related to the “true” cedars of the genus Cedrus. Instead, the various trees referred to as red cedar belong to the cypress family, Cupressaceae. The shared name emphasizes the wood’s distinctive reddish heartwood and its resistance to decay and insect damage.
Identifying the Major Species
The botanical confusion surrounding red cedar centers primarily on two commercially significant species that belong to different genera within the cypress family. The first is Eastern Red Cedar, scientifically known as Juniperus virginiana, which is native to the eastern half of North America, extending from southeastern Canada down to the Gulf of Mexico. This tree is technically a type of juniper, not a cedar, and it is relatively small, growing to heights between 30 and 40 feet.
The second major species is Western Red Cedar, or Thuja plicata, which thrives in the cool, moist temperate rainforests of the Pacific Northwest. Thuja plicata is a much larger tree, often growing to over 150 feet in height, with some specimens reaching up to 200 feet.
Distinct Physical and Aromatic Properties
The wood of red cedar species is prized for its low density and straight grain, contributing to its lightweight nature and dimensional stability. The coloration is striking, featuring a deep reddish-brown heartwood that contrasts sharply with the pale, nearly white sapwood.
The wood’s resistance to rot, decay, and insects is due to specific organic compounds known as extractives. In Western Red Cedar, this durability is linked to tropolone-related compounds like thujaplicin, which exhibit antiseptic and antifungal properties. Eastern Red Cedar’s characteristic aroma and insect-repelling quality come from sesquiterpenes, primarily cedrene and cedrol, concentrated in its heartwood. These volatile oils provide the wood’s signature pleasant fragrance while naturally deterring pests like moths and carpet beetle larvae.
Primary Uses and Applications
The natural resistance of red cedar makes it a choice for exterior construction projects where durability against the elements is important. Western Red Cedar, with its long, straight lengths of timber and stability, is widely used for siding, decking, fencing, and roofing shingles.
Eastern Red Cedar, often marketed as aromatic cedar, is primarily valued for its potent, moth-repelling fragrance, making it ideal for interior applications. It is frequently used for lining closets, crafting storage chests, and making smaller items like cedar balls and hang-ups for garment protection. This species is also used for fence posts and outdoor furniture due to its inherent toughness and rot resistance in ground contact. Beyond solid wood, the essential oils extracted from red cedar are utilized commercially in perfumery, aromatherapy, and as a natural insect repellent and larvicide.