Thuja (genus) en

Genus containing 5 species of resinous, evergreen ornamental and timber conifers of the cypress family (Cupressaceae), native to North America and eastern Asia. The genus is monophyletic and sister to Thujopsis or false arborvitae. Arborvitae are trees or shrubs, usually pyramidal in habit, with thin, scaling outer bark and fibrous inner bark, horizontal or ascending branches, and characteristically flattened, spraylike branchlet systems. Each branchlet has four rows of tiny, scalelike leaves. Juvenile leaves are much longer and needlelike and in some species may persist along with the mature foliage. Male and female reproductive structures (cones) are borne at the tips of different branchlets of the same tree, the male cones rounded and reddish or yellowish, the female very small and green or tinged with purple. They are commonly known as arborvitae (from Latin for tree of life) or thujas; several species are widely known as cedar but they are not true cedars (Cedrus).