Calocedrus (common name Incense cedar) is a genus of four species of coniferous trees in the cypress family Cupressaceae. The generic name means “beautiful cedar”.
The genus is related to the genus Thuja, and has similar overlapping scale-leaves. Calocedrus differs from Thuja in the scale leaves being in apparent whorls of four (actually opposite decussate pairs like Thuja, but not evenly spaced apart as in Thuja, instead with the successive pairs closely then distantly spaced), and in the cones having just 2 to 3 pairs of moderately thin, erect scales, rather than 4 to 6 pairs of very thin scales in Thuja.
The wood of Calocedrus is soft, moderately decay-resistant, and with a strong spicy-resinous fragrance. That of Calocedrus decurrens is the primary material for wooden pencils, because it is soft and tends to sharpen easily without forming splinters. The two Asian species were (at least in the past) in very high demand for coffin manufacture in China, due to the scent of the wood and its decay resistance. It is likely that past over-exploitation is responsible for their current rarity.
Incense cedar was the preferred hearth board of the Native Peoples of Northern California for friction fire making.
Calocedrus decurrens, the California incense cedar, is a popular ornamental tree, grown particularly in locations with cool summer climates like Britain, Washington and British Columbia. Its very narrow columnar crown in landscape settings, an unexplained consequence of the climatic conditions in these areas, is not shown by trees in their native ‘wild’ habitat. The California incense cedar is also valued for its drought tolerance. The Asian species are rarely cultivated.Attributed from: Wikipedia