The World Flora Online

SELECTED REFERENCES

Burns, R. M. and B. H. Honkala. 1990. Silvics of North America. 1. Conifers. Washington. [Agric. Handb. 654.] Canadian Forestry Service. 1983. Reproduction of Conifers. Forest. Techn. Pub. Canad. Forest. Serv. 31. Eckenwalder, J. E. 1976. Re-evaluation of Cupressaceae and Taxodiaceae: A proposed merger. Madroño 23: 237--256. Farjon, A. 1990. A Bibliography of Conifers. Königstein. [Regnum Veg. 122.] Hosie, R. C. 1969. Native Trees of Canada, ed. 7. Ottawa. Pp. 83--95. Krajina, V. J., K. Klinka, and J. Worrall. 1982. Distribution and Ecological Characteristics of Trees and Shrubs of British Columbia. Vancouver. Little, E. L. Jr. 1979. Checklist of United States Trees (Native and Naturalized). Washington. Pp. 33--36. [Agric. Handb. 541.] Rehder, A. J. 1949. Bibliography of Cultivated Trees and Shrubs Hardy in the Cooler Temperate Regions of the Northern Hemisphere. Jamaica Plain. Silba, J. 1986. Encyclopaedia Coniferae. Phytologia Mem. 8: 1--127.

Trees or shrubs evergreen (usually deciduous in Taxodium ), generally resinous and aromatic, monoecious (usually dioecious in Juniperus ). Bark fibrous and furrowed (smooth or exfoliating in plates in some Cupressus and Juniperus species). Lateral branches well developed, similar to leading shoots, twigs terete, angled, or flattened dorsiventrally (with structurally distinct lower and upper surfaces; Thuja , Calocedrus ), densely clothed by scalelike leaves or by decurrent leaf bases; longest internodes to 1 cm; buds undifferentiated and inconspicuous (except in Sequoia ). Roots fibrous to woody (bearing aboveground "knees" in Taxodium ). Leaves simple, usually persisting 3--5 years and shed with lateral shoots (cladoptosic) (shed annually in Taxodium ), alternate and spirally arranged but sometimes twisted so as to appear 2-ranked, or opposite in 4 ranks, or whorled, deltate-scalelike to linear, decurrent, sessile or petioled; adult leaves appressed or spreading, often differing between lateral and leading shoots (twigs heterophyllous), sometimes strongly dimorphic on each twig ( Thuja , Calocedrus ) with lateral scale-leaf pairs conspicuously keeled; juvenile leaves linear, flattened, spreading; often with solitary abaxial resin gland; resin canal present. Pollen cones maturing and shed annually, solitary, terminal (rarely in clusters of 2--5, axillary in Juniperus communis ; usually in terminal panicles in Taxodium ), simple, spheric to oblong; sporophylls overlapping, bearing 2--10 abaxial microsporangia (pollen sacs); pollen spheric, not winged. Seed cones maturing in 1--2 seasons, shed with short shoots or persisting indefinitely on long-lived axes (shattering at maturity in Taxodium ), compound, solitary, terminal (rarely in clusters of 2--5, axillary in Juniperus communis ); scales overlapping or abutting, fused to subtending bracts with only bract apex sometimes free; each scale-bract complex peltate, oblong or cuneate, at maturity woody or fleshy, with 1--20 erect (inverted with age in Sequoia and Sequoiadendron ), adaxial ovules. Seeds 1--20 per scale, not winged or with 2--3 symmetric or asymmetric wings; aril lacking; cotyledons 2--9.

Plantes ligneuses, dioïques ou monoïques, ramifiées, sans canaux résinifères sauf dans l'écorce.'Feuilles'opposées-décussées ou verticillées par 3, souvent hétéromorphes : feuilles juvéniles aciculaires-subulées, feuilles adultes généralement écailleuses et apprimées.'Strobiles petits, terminaux ou latéraux, à sporophylles opposés ou verticillés et nus. Écailles staminales à 2-5 sacs polliniques sur la face inférieure; grains de pollen non ailés. Écailles ovulifères à 1-plusieurs ovules, orthotropes et unitégumentés. Cônes murs ligneux ou charnus, généralement à plusieurs graines à spermoderme dur.\n\t\t\tSeize genres et environ 130 espèces, répandues dans les régions tempérées et subtropicales surtout de l'hémisphère boréal; quelques espèces dans les montagnes de la zone tropicale.\n\t\t\tParmi les Conifères introduits au Congo belge1, signalons spécialement le genre'Cupressus'L. dans les régions orientales montagneuses.'C. lusitanica Mill., sous formes diverses (hybrides) est le plus communément cultivé. Peu exigeant au point de vue des qualités du sol et des conditions du climat, il constitue des boisements parfois très étendus; c'est actuellement celui qui est multiplié avec le plus de chances de succès.

Staminate strobili in small cones, terminal or on short lateral shoots; scales few, subpeltate, bearing 2-many pollen sacs Leaves on adult plants scale-like, appressed and apparently decussate; on juveniles subulate, spreading and spirally arranged or irregularly disposed Trees or shrubs, monoecious or dioecious Mature female strobilus usually a cone with woody peltate persistent opposite scales, sometimes a berry-like fruit with fleshy confluent scarcely distinguishable scales Ovules 1-many per scale, erect Female strobili of 1–12 scales; scales woody or fleshy Leaves on adult plants scale-like, appressed and apparently decussate; on juveniles subulate, spreading and spirally arranged or irregularly disposed Trees or shrubs, monoecious or dioecious Mature female strobilus usually a cone with woody peltate persistent opposite scales, sometimes a berry-like fruit with fleshy confluent scarcely distinguishable scales Ovules 1-many per scale, erect Female strobili of 1–12 scales; scales woody or fleshy

Female cones small, the scales opposite or ternate, apparently without subtending bracts, woody and distinct, or often ± coalescent to form a berry-like or drupe-like cone at maturity; microsporophylls of male cones few, opposite; monoecious or dioecious evergreen trees or shrubs; lvs opposite or whorled, crowded and often overlapping, needle-like or more often scale-like, sometimes dimorphic. 15/140.

Trees or shrubs evergreen, monoecious or dioecious. Leaves decussate or in whorls of 3, scalelike and then often dimorphic with flattened facial leaves and keeled lateral leaves, or needlelike particularly in juvenile plants, often with an abaxial resin gland. Pollen cones terminal or axillary, solitary, maturing and shed annually; microsporophylls 6-16, decussate or whorled, each bearing (2 or)3-6(-9) pollen sacs; pollen wingless. Seed cones usually terminal, solitary, globose, ovoid, or oblong, dehiscent or indehiscent when mature in 1st or 2nd(or 3rd) year; cone scales developing after ovules originate in bract axils; bracts almost completely enveloped by cone scales, free only at apex; ovules 1-numerous per bract axil, erect; cone scales of mature cones 3-16, flat or peltate, woody, ± leathery, or succulent, 1-20-seeded. Seeds winged or not; wings derived from seed coat. Cotyledons usually 2, rarely 3-6. Germination epigeal.