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Trees evergreen; trunk monopodial, straight; branches nearly whorled; branchlets ridged and grooved, with each leaf borne on a persistent, peglike base (pulvinus); short branchlets absent; winter buds ovoid, conical, or subglobose, resinous or not, scales on terminal buds recurved or not, persistent at base of branchlets. Leaves spirally arranged, spreading radially, or directed forward on upper side of branchlets and spreading on lower side, each inserted on a petiolelike pulvinus, linear, straight or curved, quadrangular, broadly rhombic, or flattened in cross section, stomatal lines adaxial or on each surface, vascular bundle 1, resin canals 2, sometimes small and discontinuous. Pollen cones solitary in leaf axils, rarely terminal, ellipsoid or cylindric; pollen 2-saccate. Seed cones solitary, pendulous at maturity, ovoid-cylindric or cylindric, rarely ovoid, maturing in 1st year. Seed scales thinly woody, leathery, or papery, with margin entire, denticulate, or undulate toward apex, persistent. Bracts included, small. Seeds obovoid or ovoid; wing long, membranous. Cotyledons 4-9(-15). Germination epigeal. 2n = 24*.
Evergreen, conic or pyramidal, resinous trees with thin scaly bark and whorled branches. Short shoots 0. Winter buds generally not resinous, ovoid or conic, rounded to subacute. Lvs solitary, spirally arranged, ± 2-ranked (except on young erect shoots), inserted on a persistent peg-like projection of the shoot (thus older leafless part of shoots rough), linear and flat to quadrangular, green above and with 2 greyish stomatal bands on lower (inverted adaxial) surface, or stomatiferous on all 4 sides, usually with 2 marginal resin ducts. ♂ strobili (cones) axillary, cylindric or catkin-like, yellow to red, erect or pendent. ♀ cones terminal, ripening in first year, generally purplish before maturity, pendent; ovuliferous scales always much > bract scales, rather thin; ovules 2 to each scale. Mature cones not disintegrating, pendulous, generally cylindric. Seed winged.
Monoecious trees. Branches whorled. Leaves linear, 4-angled, helically arranged but often twisted to form regular ranks; leaf bases decurrent and persistent as 'pegs'. Male cones axillary, cylindrical. Female cones terminal on short branches from uppermost lateral branches, pendulous, cylindrical, ripening and shedding seeds in first year but often remaining on the tree for several years afterwards. Seeds with a large membranous wing.
Male and female cones terminating twigs of the previous year’s growth; female cones pendulous, with persistent scales much exceeding the bracts; evergreen trees, the quadrangular lvs jointed at the base to a short, projecting sterigma that persists on the denuded branch; resin-ducts 2 in each lf; 2n=24. 30+, N. Temp
