Chamaecyparis
11: 329. 1841.
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.
Distribution
North America, e Asia.
Discussion
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.
Species 6–7 (3 in the flora).
Selected References
None.
Key
| 1 | Seed cones 4-9 mm broad; leaves usually with circular abaxial glands; Atlantic and Gulf coasts. | Chamaecyparis thyoides |
| 1 | Seed cones 8-12 mm broad; leaves with linear to circular abaxial glands or glands absent; Pacific Coast. | > 2 |
| 2 | Seed cones with 5-9 scales, opening at end of first year, not notably resinous; leaves usually with linear glands; facial leaves of branchlets frequently separated from each other by paired bases of lateral leaves. | Chamaecyparis lawsoniana |
| 2 | Seed cones with 4-6 scales, sometimes remaining closed at end of first year, becoming resinous; leaves usually without glands, these circular when present; apices of facial leaves of branchlets often overlapping the base of next facial leaf. | Chamaecyparis nootkatensis |