Trees evergreen; branches regularly whorled; branchlets opposite (rarely whorled), with orbicular, depressed leaf scars and persistent bud scales at base; short branchlets absent; winter buds usually 3 at apex of branchlets, subglobose, ovoid, or conical, often resinous. Leaves spirally arranged, radially spreading, or pectinately arranged in lateral sets, linear, straight or curved, flattened, grooved adaxially, stomatal bands 2, abaxial, vascular bundle 1, resin canals 2(-10 outside China), marginal (in hypodermis) or median (in mesophyll), rarely submedian, base twisted. Pollen cones borne in leaf axils of previous year’s branchlets, pendulous, narrowly ellipsoid or oblong when young, finally cylindric; pollen 2-saccate. Seed cones pedunculate or sessile, erect, ovoid-cylindric or shortly cylindric, maturing in 1st year. Seed scales closely overlapping, often reniform, trapeziform, or flabellate, woody, base narrowed, deciduous at maturity. Bracts oblong, obcordate, or obovate, with exserted or included, sometimes reflexed cusp. Seeds borne in a membranous cup, obliquely ovoid or cuneate-oblong; wing well developed, persistent, cuneate-dolabriform or oblong-cuneate. Cotyledons (3 or)4-8(-12). Germination epigeal. 2n = 24*.
Trees evergreen, crown usually spirelike to conic, sometimes flat to round topped in age. Bark initially thin, smooth, bearing resin blisters, in age furrowed and/or flaking in plates. Branches whorled, irregular internodal branches occasionally produced by epicormic sprouting (growing from a dormant bud); short (spur) shoots absent; leaf scars prominent, ± circular to broadly elliptic, flush with twig surface, slightly depressed, or slightly raised evenly all around. Buds ovate or oblong, resinous or not, apex rounded or pointed. Leaves borne singly, persisting 5 or more years, spirally arranged but often proximally twisted so as to appear either 1-ranked (pointing up like toothbrush bristles) or 2-ranked, sessile, typically constricted and often twisted above the somewhat broadened base, sheath absent; leaves on vegetative branches flattened, frequently grooved adaxially, usually notched to rounded at apex; leaves on fertile branches sometimes appearing 4-sided, upright, sharp-pointed to rounded at apex; resin canals 2. Cones borne on year-old twigs. Pollen cones grouped, ovate or oblong-cylindric, leaving gall-like protuberances after falling, yellow to red, green, blue, or purple. Seed cones maturing in 1 season, erect, ovoid to oblong-cylindric or cylindric, not falling whole but scale by scale, cone axis persisting as an erect "spike" on branch; scales shed individually, fan-shaped, lacking apophysis and umbo; bracts included to exserted. Seeds winged, the wing-seed juncture bearing resin sac; cotyledons 4--10. x =12.
"Male cones ovoid or short-cylindric, pendulous on short stalks from the axils of lvs of the preceding year, subtended by conspicuous bud-scales; female cones erect, cylindric, typically confined to the upper part of the tree, the scales individually deciduous at maturity, so that the cone rarely falls intact; bracts longer than the ovuliferous scales at anthesis, but often surpassed and hidden at maturity; evergreen trees, the lvs attached directly to the twigs and leaving a smooth, round scar on falling; 2n=24. 40, N. Temp."
Liu, T. S. 1971. A Monograph of the Genus Abies. Taipei. Matzenko, A.E. 1968. Conspectus generis Abies Mill. Novosti Sist. Vyssh. Rast. 5: 9--12.
In the key below, all descriptions are based on leaves from vegetative branches of the lower crown unless otherwise noted.
|Fir [Latin name of a European fir]|