Yellow-Cedar: The Tree

WHAT'S IN A NAME?

The common and scientific names for yellow-cedar are both in flux. Here's a short discussion of both.

Common name

There are a number of common and rare names (e.g., Nootka cypress, canoe-cedar) applied to this tree. The commonly used names use various combinations of "Alaska" and/or "yellow", followed by "cedar" or in some cases "cypress".

"Alaska-cedar" is the accepted common name by the USFS. This name does not help foster a relationship with Canadians, however. Remember, the species was first discovered by Archibald Menzies on the Vancouver expedition in British Columbia and named for the Nootka Sound area of western Vancouver Island. The bulk of the acreage and supply for this tree exist in British Columbia, not Alaska. Thus, Canadians have a right to object to the use of names such as Alaska-cedar or Alaska yellow-cedar.

The word "yellow" is appropriate in the common name because of the reference to the distinctive yellow color of the wood.

If the word "cedar" is used, note that a hyphen must be used, as in "yellow-cedar", because this species is a "false cedar" and not a "true cedar". True cedars are in the Pine family (Pinaceae) and are represented by old world species with needles in the genus Cedrus. Use of the hyphen follows the same logic as with "Douglas-fir", which is not a true fir.

Both "yellow-cedar" and "yellow cypress" are used in Canada.

See the last few sentences in the discussion on the scientific name below, which make a case for the name "cypress" and over "cedar".

Scientific name

The taxonomic status, and therefore the scientific name, of yellow-cedar is in question partially because of the discovery of a tree species with close phylogenetic affinity in northern Vietnam, Xanthocyparis vietnamensis Farjon & Hiep. (Farjon et al. 2002). One recommendation is for yellow-cedar to join the Vietnamese tree as the only members in a genus, but whether the new name Xanthocyparis nootkatensis Farjon & Hiep or an older name Callitropsis nootkatensis (D. Don) Orest. (Little et al. 2004) is adopted will be determined at the next International Botanical Congress in 2011 (Mill and Farjon 2006). This debate is essentially about whether the name "Callitropsis" was used properly in the 1800s following the rules of botanical nomenclature. There is yet another complication: some botanists prefer to return the tree to the genus Cupressus, which interestingly, was the original name for this tree, Cupressus nootkatensis. An excellent paper by Little (2006) covers the genetic and morphological evidence to suggest that yellow-cedar, the Vietnamese cypress, and the various new world cypressus species (Cupressus) are all closely related. Thus, yellow-cedar is more closely related to these cypresses trees than it is to species in Chamaecyparis. Some change in the scientific name for yellow-cedar is inevitable.

References

Farjon, A; Hiep, N.T., Harder; D.K., Loc; P.K.; Averyanov, L. 2002. The new genus and species in Cupressaceae (Coniferales) from northern Vietnam, Xanthocyparis vietnamensis. Novon. 12: 179-189. Little, D.P. 2006. Evolution and circumscription of the true cypresses (Cupressaceae: Cupresssus). Systematic botany. 31:461-480. Little, D.P.; Schwarzbach, A.E.; Adams, R.P.; Hsieh, C.F. 2004. The circumscription and phylogenetic relationships of Callitropsis and the newly described genus Xanthocyparis (Cupressaceae). Amer. J. Bot. 91: 1872-1881. Mill, R.R.; Farjon, A. 2006. Proposal to conserve the name Xanthocyparis against Callitropsis Oerst. (Cuppressaceae). Taxon. 55: 229-231.

Natural Range

Yellow-cedar grows along the Pacific Coast of North America from the California-Oregon border to Prince William Sound in Alaska. It is known as a high elevation species in most of its range, only growing down to sea level in the north.  The widespread forest decline and mortality, discussed in the detection section, is limited to part of its range in Southeast Alaska and an adjacent area of British Columbia. The precise distribution of yellow-cedar in Alaska is not well know although we are actively pursuing that topic. We used field plot data from USFS Forest Inventory and Analysis (FIA) to construct a coarse presence/absence map of yellow-cedar

Historical and Cultural Uses

Value and Demand

Although the natural range is more extensive, occurring south to California, yellow-cedar is primarily an important timber species in British Columbia and Alaska.  The wood has a number of desirable characteristics, particularly exceptional strength and decay resistance.  This makes yellow-cedar a preferred wood for engineering purposes suitable in the exterior environment.  It has long been used by boat builders, but also is used for bridges, decks, and fencing.  Yellow-cedar is also viewed as a superior carving wood because of similar densities between spring and summer wood (e.g., reduced grain effect).  Also, yellow-cedar is one of the best woods in the world for wooden arrow shafts because of its straight grain and strength properties.

The light color appearance of the wood appeals to the Japanese market where considerable volumes are exported at high values and used in home construction.  Yellow-cedar is also viewed as an alternative to Hinoki cedar (another Chamaecyparis species native to Japan that is now in short supply).  There, yellow-cedar is used in the construction and rebuilding of temples in Japan. 

Yellow-cedar is also used as an ornamental tree, with a number of interesting cultivars.  Probably best known is “Leyland cypress” which is actually a fertile hybrid between yellow-cedar and Monterrey cypress. 

Natural history

In southeast Alaska, yellow-cedar is abundant on wet, poorly drained sites near bogs and peatlands.  It mixes with other tree species (particularly western hemlock) on soils with better drainage, where it attains its greatest stature, but apparently is less competitive because of its slower growth or poor reproduction there.  It does not reproduce prolifically from seed, and on wet, open-canopy forests, spreads as a form of cloning by the rooting of lower branches (layering).

Yellow-cedar is a slow-growing defensive tree with few insect and disease enemies.  It is capable of reaching great longevity, with trees growing over 1,000 years old, but is dying in large numbers in portions of southeast Alaska and nearby British Columbia.  We are investigating this extensive tree death with the goal of identifying some unique environmental susceptibility of yellow-cedar (e.g., what is its Achilles’ heel?) in an attempt to explain the primary cause of the problem.

Yellow-cedar Bibliography

Several years ago, we produced an annotated bibliography of yellow-cedar to list all known scientific information on the tree.

• yellow-cedar references