Types of Cedar: True Cedars vs Trees Called Cedar

The types of cedar fall into two groups: true cedars of the genus Cedrus, and dozens of unrelated trees that carry "cedar" as a common name. Wikipedia describes Cedrus as one to three species depending on the botanist, with three commonly recognized:

• Atlas cedar (Cedrus atlantica) - Atlas Mountains of North Africa; silver-blue needles on the popular garden forms (Planet Natural).
• Deodar cedar (Cedrus deodara) - western Himalayas; drooping branch tips.
• Cedar of Lebanon (Cedrus libani) - Mediterranean mountains. Wikipedia's list of cedars adds the Cyprus cedar (C. brevifolia), which some treat as a separate species.

All are Pinaceae, the pine family. Wikipedia gives the genus a height of 30 to 40 m (rarely 65 m), needles in tufts of 15 to 45 on short shoots, and barrel-shaped cones that stand upright and break apart on the branch to release winged seeds, like a fir. None is native to the Americas, so in North America a true cedar is almost always a planted ornamental.

The cedar in lumber yards, fences and closets is almost always one of these cypress-family (Cupressaceae) trees, as listed by Wikipedia:

• Western red cedar (Thuja plicata) - Pacific Northwest; Buffalo Lumber says it matures to 200 feet with a 6 to 13 foot trunk, and calls it the most requested siding species. Western red cedar wood
• Northern (eastern) white cedar (Thuja occidentalis) - northeastern US and eastern Canada; small trees of 30 to 60 feet used for shingles and fencing (Buffalo Lumber).
• Eastern red cedar (Juniperus virginiana) - botanically a juniper; the aromatic wood of cedar chests and closet linings. Eastern red cedar wood
• Atlantic white cedar (Chamaecyparis thyoides) and Port Orford cedar (Chamaecyparis lawsoniana) - false cypresses rather than cedars.
• Incense cedar (Calocedrus decurrens) - California, southern Oregon and western Nevada; Buffalo Lumber says nearly all modern wooden pencils are made from it.
• Alaska yellow cedar (Cupressus nootkatensis) - California-Oregon border to southern Alaska; pale to golden yellow wood.

Buffalo Lumber also lists inland red cedar, which is the same species as western red cedar grown further east in the Rockies: lighter in color, with more knots.

• Spanish cedar (Cedrela odorata) - a tropical American hardwood in the mahogany family, Meliaceae; it is the cedar of cigar boxes (Wikipedia lists Cedrela as "cigar-box cedar"). The USDA Wood Handbook ranks its heartwood "resistant" to decay.
• Australian red cedar (Toona ciliata) - also Meliaceae.
• Saltcedar (Tamarix) - unrelated to any of the above.
• Japanese cedar (Cryptomeria japonica) - a cypress-family conifer.

The practical point: "cedar" on a label tells you little. Ask for the botanical name, because the wood of a juniper, a Thuja and a Cedrela behaves very differently.

None of the top-ranking cedar pages give numbers. The USDA Wood Handbook does. Side hardness below is from Table 5-3b at 12% moisture (eastern redcedar only has a green-wood value in that table), and every species listed is in the "resistant" heartwood decay group of Table 14-1:

• Northern white cedar - 320 lbf, specific gravity 0.31
• Atlantic white cedar - 350 lbf, 0.32
• Western red cedar - 350 lbf, 0.32
• Incense cedar - 470 lbf, 0.37
• Alaska yellow cedar - 580 lbf, 0.44
• Port Orford cedar - 630 lbf, 0.43
• Eastern red cedar - 650 lbf (green), 0.44

For comparison, red oak is 1,290 lbf in the same table, so every cedar dents far more easily than a hardwood floor. What the cedars offer is light weight and decay resistance without chemical treatment.

Western red cedar is the default outdoor cedar: Buffalo Lumber ranks it first for durability and longevity, and it is widely stocked in Clear, Near Clear and Tight Knot grades. Incense cedar and Alaska yellow cedar weather about as well and are the usual alternatives; inland red cedar is the budget, knotty version.

Three rules from the USDA Wood Handbook matter more than the species choice:

• Use heartwood. The handbook says untreated sapwood of essentially all species has low decay resistance, so pale sapwood edges on a cedar board will rot first.
• Keep it off the soil. The table's footnote warns that resistance may be lower in ground contact and in warm, humid climates; for posts in the ground, use lumber treated for ground contact (see our treated wood for decks guide).
• Expect dents. At 350 lbf, western red cedar suits siding, fences and pergolas better than a heavily used deck surface.

• Needles or scales? True cedars have needles in tufts and upright barrel-shaped cones (Wikipedia). The Thuja, Chamaecyparis, Calocedrus and juniper "cedars" have small scale-like leaves; Planet Natural describes incense cedar foliage as dense and almost scale-like.
• Bark. Planet Natural describes western red cedar bark as reddish-brown and fibrous, and northern white cedar bark as peeling.
• Wood color and smell. Eastern red cedar heartwood is purplish red with pale streaks and small knots and a strong closet smell; western red cedar is reddish to pinkish brown, straight and coarse-grained, and very light (our species pages have the end-grain details).
• Weight. Alaska yellow cedar is noticeably heavier and paler than western red cedar (specific gravity 0.44 against 0.32).

A photo of the foliage, the bark or a cut end in WoodLens will suggest which "cedar" you have. See also our tree identification hub.

This page was drafted with AI help, and every fact was checked against the sources listed on the page.