Trees (rarely shrubs). Branchlets terete or rhombic in cross section, in fan-shaped or pinnately flattened sprays. Leaves opposite in 4 ranks. Adult leaves usually appressed, lateral and facial pairs similar, closely overlapping, scalelike, free portion of long-shoot leaves to ca. 7 mm; abaxial glands present or absent, circular to linear. Pollen cones with 2--3 pairs of sporophylls, each sporophyll with 2--4 pollen sacs. Seed cones maturing and opening in 1--2 years, nearly globose, glaucous, 4--12 mm; scales persistent, 2--5(--6) pairs, valvate, peltate or basifixed, thick and woody, terminal pair often fused. Seeds 1--4 per cone scale, lenticular, equally 2-winged; cotyledons 2--3. x = 11.
Two Japanese species are widely cultivated and may become established locally. Chamaecyparis obtusa (Siebold & Zuccarini) Endlicher (hinoki-cypress) has obtuse, glandless leaves and seed cones ca. 10--12 mm broad; C . pisifera (Siebold & Zuccarini) Endlicher (sawara-cypress) has acuminate, obscurely glandular leaves and seed cones 6--8 mm broad. Cultivated juvenile forms of several species have been referred to by the superfluous Retinospora Siebold & Zuccarini. Some authors include species of Chamaecyparis in the genus Cupressus .
Female cones subglobose, woody, dehiscent, with 3-6 pairs of ovuliferous scales each bearing 2-5 ovules, the scales becoming peltate and polygonal, pointed or elevated in the middle; seeds winged; microsporophylls few; monoecious trees with small, appressed, scale-like, decussately opposite lvs, the lateral ones folded and upper and lower flat or rounded, often with a resin-gland; branchlets numerous from the axils of the lateral lvs, forming ±flattened sprays; 2n=22. 6, N. Temp.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.