The genus Cupressus is one of several genera within the family Cupressaceae that have the common name cypress; for the others, see cypress. It is considered a polyphyletic group. Based on genetic and morphological analysis, the Cupressus genus is found in the Cupressoideae subfamily. The common name comes from Old French cipres and that from Latin cyparissus, which is the latinization of the Greek κυπάρισσος (kypárissos).
As currently treated, these cypresses are native to scattered localities in mainly warm temperate regions in the Northern Hemisphere, including western North America, Central America, northwest Africa, the Middle East, the Himalayas, southern China and northern Vietnam.
As with other conifers, extensive cultivation has led to a wide variety of forms, sizes and colors, that are grown in parks and gardens throughout the world. They are evergreen trees or large shrubs, growing to 5–40 m tall. The leaves are scale-like, 2–6 mm long, arranged in opposite decussate pairs, and persist for three to five years. On young plants up to two years old, the leaves are needle-like and 5–15 mm long. The cones are 8–40 mm long, globose or ovoid with four to 14 scales arranged in opposite decussate pairs; they are mature in 18–24 months from pollination. The seeds are small, 4–7 mm long, with two narrow wings, one along each side of the seed.
Many of the species are adapted to forest fires, holding their seeds for many years in closed cones until the parent trees are killed by a fire; the seeds are then released to colonize the bare, burnt ground. In other species, the cones open at maturity to release the seeds.
Many species are grown as decorative trees in parks and, in Asia, around temples; in some areas, the native distribution is hard to discern due to extensive cultivation. A few species are grown for their timber, which can be very durable. The fast-growing hybrid Leyland cypress, much used in gardens, draws one of its parents from this genus (Monterey cypress Chamaecyparis macrocarpa); the other parent, Nootka cypress, is also sometimes classified in this genus, or else in the separate genus Callitropsis, but in the past more usually in Chamaecyparis.Attributed from: Wikipedia