The common name “cedar” frequently appears in discussions of North American forests, but the term carries significant botanical complexity. While many native trees are widely known as cedars, this designation is based primarily on the aromatic, durable wood they produce. Taxonomically, the trees native to North America that bear the name “cedar” are distinct from the true cedars of the world. This difference highlights the distinction between colloquial language and scientific classification.
The Taxonomic Distinction: True Cedars and North American Relatives
The designation of a true cedar belongs exclusively to the genus Cedrus, which is not native to the Western Hemisphere. These trees belong to the Pine family (Pinaceae) and are naturally found in the mountainous regions of the Mediterranean and the western Himalayas.
Cedrus species possess specific physical features that set them apart from their North American namesakes. They have short, needle-like leaves that grow in dense clusters on specialized short shoots called spur shoots. Their cones are large, barrel-shaped, grow upright on the branches, and disintegrate upon maturity to release their winged seeds.
In contrast, the native North American trees referred to as cedar belong to the Cypress family (Cupressaceae). Because of this fundamental difference, botanists often refer to these North American species as “false cedars.” This common naming practice is rooted in the long history of using the wood for its fragrant, rot-resistant qualities, which mimic the properties of Cedrus wood.
Prominent Native North American Species
The native trees adopting the cedar moniker are found across the continent and represent several distinct genera within the Cypress family. The widespread genus Thuja includes the well-known Western Red Cedar (Thuja plicata) and the Northern White Cedar (Thuja occidentalis). These Thuja species are characterized by small, overlapping, scale-like leaves pressed tightly against the branchlets, forming flattened, fan-like sprays of foliage.
Another genus is Juniperus, exemplified by the Eastern Red Cedar (Juniperus virginiana), a species common throughout the eastern and central United States. Junipers often display two types of foliage: mature trees have scaly leaves, while young trees and juvenile growth on older trees feature sharp, needle-like leaves. The reproductive structures are also markedly different, as the female cones of Juniperus are small, fleshy, and appear as distinctive blue, berry-like structures.
The Incense Cedar (Calocedrus decurrens) represents a third significant genus, primarily located in western North America. This tree is noted for its beautiful, columnar shape and its flattened sprays of dark green, scale-like leaves that emit a strong, aromatic odor when crushed. Its cones are small and cylindrical, composed of six paired scales that look somewhat like miniature duck bills. These three genera—Thuja, Juniperus, and Calocedrus—form the core of what the average person in North America identifies as cedar.
Geographic Distribution and Identification Features
The three major native “cedar” genera are distinguished by their geographic range and specific physical characteristics. The Western Red Cedar (T. plicata) is a towering species found mainly in the cool, moist climates of the Pacific Northwest, extending from Alaska down to Northern California. Its eastern counterpart, the Northern White Cedar (T. occidentalis), is distributed across the Great Lakes region and the northeastern United States and Canada, often thriving in moist soil and swamps.
The Incense Cedar (C. decurrens) has a restricted western range, typically inhabiting mountainous areas from central Oregon south through California. It is easily differentiated from Thuja by its unique, elongated cones and its tendency to maintain a deep green color year-round. The Eastern Red Cedar (J. virginiana) is a hardy pioneer species that dominates much of the eastern half of the continent, tolerating a wide variety of soil conditions.
Distinguishing these genera relies heavily on cone structure. Juniperus is unique because its female cones are small, round, and fleshy, resembling blue berries. In contrast, Thuja and Calocedrus produce small, woody, dry cones that open to release seeds. Observing the foliage shape—flattened sprays for Thuja and Calocedrus versus the more cylindrical, often prickly new growth of Juniperus—provides a straightforward method for separation.