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| 1 Leaves cordate-auriculate at base; [subgenus Magnolia]. |
| ..2 Leaves glaucous and finely appressed-pubescent beneath; buds and twigs pubescent; [section Macrophylla; or genus Metamagnolia]. |
| ....3 Conelike aggregate fruit (follicetum) 2.5-6.5 cm long, 1.5-4 cm in diameter; leaf blades 17-56 cm long; stamens 170-350; pistils 20-25 (-50); small tree (to 12 m tall); [of Panhandle FL] |
| ....3 Conelike aggregate fruit (follicetum) 5-8 cm long, 5-7 cm in diameter; leaf blades 50-110 cm long; stamens (300-) 350-580; pistils (44-) 50-80; medium to large tree (to 32 m tall); [widespread, but not of Panhandle FL] |
| ..2 Leaves green and glabrous beneath; buds and twigs glabrous; [section Tuliparia; or genus Paramagnolia]. |
| ......4 Stamens 8-15 mm long; leaves (most of them) over 25 cm long; conelike aggregate fruit (follicetum) 6.5-11 (-14) cm long; [of the Mountains and Piedmont] |
| ......4 Stamens 4-8 (-10.5) mm long; leaves (most of them) < 25 cm long; conelike aggregate fruit (follicetum) 3.5-5.5 (-6) cm long; [of the Coastal Plain] |
| 1 Leaves cuneate to rounded (subcordate) at base. |
| ........5 Leaves evergreen, coriaceous in texture, glossy dark green above as if varnished, rusty tomentose or green beneath; [section Magnolia; or genus Magnolia] |
| ........5 Leaves variably evergreen to deciduous, herbaceous or subcoriaceous in texture, medium green above with a slightly glossy or dull finish; glaucous or green beneath. |
| ..........6 Leaves evergreen to deciduous, aromatic when fresh, 8-20 cm long, elliptic, strongly glaucous beneath; [section Magnolia; or genus Magnolia]. |
| ............ 7 Leaves evergreen; previous year's stems densely pubescent; mature leaves with pubescent midveins; flowers opening near sundown (2-5 hours later than var. virginiana); medium to large tree, to >20 m tall; [of the Gulf Coast and inland, north and east to s. SC (e. NC?)] |
| ............ 7 Leaves evergreen to deciduous (at least tardily); previous year's stems glabrous; mature leaves with few hairs along the midvein below; flowers opening mid-afternoon; shrub to multi-stemmed small tree, to 10 m (rarely to 15 m) tall; [of the Atlantic Coastal Plain and inland, south and west to s. SC and w. NC] |
| ..........6 Leaves deciduous, non-aromatic, 3-80 cm long, either ovate, obovate, or oblanceolate, green beneath. |
| ............ ..8 Leaf base cuneate-attenuate; leaf blade obovate or oblanceolate (broader toward the tip); buds either glabrous or sericeous. |
| ............ ....9 Leaf blades 3-16 cm long; buds densely sericeous; [alien]; [section or genus Yulania] |
| ............ ....9 Leaf blades (15-) 35-50 (-80) cm long; buds glabrous; [native]; [section Rytidospermum; or genus Houpoea] |
| ............ ..8 Leaf base rounded to subcordate (often cuneate to widely cuneate in M. acuminata var. subcordata); leaves 10-30 cm long, broader near the middle or toward the base, borne scattered along the twig; buds pubescent; [section Tulipastrum; or genus Yulania]. |
............ ......10 Twigs of the current year glabrous; petals greenish or greenish-yellow; medium to large tree |
| ............ ......10 Twigs of the current year pubescent, or at least with persistent hair-bases, petals golden-yellow above, light-yellow below; small tree (rarely larger) |