Plants annual. Culms (0.5) 1-3 (6) m tall, (0.5) 1-5 cm thick. Blades mostly 30-90 cm long, 2.5-12 cm wide. Pistillate inflorescences rames or spikes, usually shortly pedunculate (sometimes sessile), solitary, 4-30 (40) cm long, (0.5) 1-10 cm thick, with 2 or more rows of paired spikelets, hence the spikelets 4 or more ranked, rarely terminating in an unbranched staminate inflorescence. Caryopses concealed in fruitcases (wild taxa) or exposed (domesticated taxon); fruitcases of wild taxa distichous, triangular in side view; domesticated taxon without fruitcases, glumes reduced and shallow or collapsed and embedded in the rachis. Staminate panicles 10-25+ cm, with 1-60 (235) branches, internodes 1.5-8.2 mm; spikelets 9-14 mm long, 2.5-5 mm wide; lower glumes rounded dorsally, flexible, translucent, papery, loosely enclosing the upper glumes, the 2 lateral-veins subequal to the others, not winged. 2n = 20.

Distribution

Ga., Va., Conn., R.I., Calif., Idaho, Oreg., Wash., Ala., Ark., Colo., Iowa, Ill., Ind., Kans., Ky., La., Mass., Md., Maine, Mich., Minn., Mo., Miss., Mont., N.C., N.H., N.J., N.Mex., N.Y., Ohio, Pa., Puerto Rico, S.C., Tenn., Tex., Utah, Virgin Islands, Vt., Wis., W.Va., Wyo., Ont., Que., Fla., Nebr., Ariz., Nev.

Discussion

Of the five subspecies of Zea mays, only the domesticated subspecies, Z. mays subsp. mays, is widely grown outside of research programs. Three wild subspecies are treated here, albeit briefly, because of their importance as genetic resources for Z. mays subsp. mays.

Selected References

None.

Key

1 Pistillate inflorescences cylindrical spikes, 2-5(10) cm thick, with 8-24+ rows of spikelets pairs, each inflorescence tightly and permanently enclosed by several leaf sheaths and a large prophyll, not disarticulating at maturity; caryopses 60-1000+, not concealed by the glumes; staminate panicle branches not disarticulating below the sessile spikelets, lacking abscission layers; central axis of the staminate panicles polystichous, much thicker than the lateral branches; obligate domesticate Zea mays subsp. mays
1 Pistillate inflorescences cylindrical, distichous rames, less than 1 cm thick, with 2 rows of spikelet pairs, each rame usually enclosed by a single leaf sheath and a prophyll, disarticulating at maturity into fruitcases; caryopses 4-15, each one concealed within a fruitcase; staminate panicles composed of rames that disarticulate below the sessile spikelets and have evident abscission layers; central axis of the staminate panicles similar in width to the rames; in the Flora region, wild taxa are known only from research plantings. > 2
2 Staminate spikelets (6.6)7.5-10.5 mm long; fruitcases 6-10 mm long, 4-6 mm wide; staminate panicles with 1-35+ ascending to divergent, rather stiff branches Zea mays subsp. mexicana
2 Staminate spikelets 4.6-7.2(7.9) mm long; fruitcases 5-8 mm long, 3-5 mm wide; staminate panicles usually with 10-100(235) divergent to nodding branches. > 3
3 Leaves pubescent; staminate panicles with (2)10-100(235) branches Zea mays subsp. parviglumis
3 Leaves glabrous or almost so; staminate panicles usually with fewer than 40 branches Zea mays subsp. huehuetenangensis

"decumbent" is not a number."elongated" is not a number."thin" is not a number.

... more about "Zea mays"
anatomy +  and kranz +
Hugh H. litis +
1 (?) +  and 3 (?) +
disarticulating +
keeled +  and rounded +
pseudopetiolate +  and branching +
divergent +  and parallel +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
non-radiate +  and radiate +
well-developed +
30 cm300 mm <br />0.3 m <br /> (90 cm900 mm <br />0.9 m <br />) +
usually linear +  and lanceolate occasionally ovate +
reduced +
2.5cm;12cm +
spikelike +
reduced +
subspherical +  and dorsally compressed +
always much thicker +
branching +  and monopodial +
several to many +  and solitary +
purple +  and reddish +
100 cm1,000 mm <br />1 m <br /> (300 cm3,000 mm <br />3 m <br />) +
ascending +  and erect +
7 cm70 mm <br />0.07 m <br /> (600 cm6,000 mm <br />6 m <br />) +
woody +  and succulent +
1 cm10 mm <br />0.01 m <br /> (5 cm50 mm <br />0.05 m <br />) +
Ga. +, Va. +, Conn. +, R.I. +, Calif. +, Idaho +, Oreg. +, Wash. +, Ala. +, Ark. +, Colo. +, Iowa +, Ill. +, Ind. +, Kans. +, Ky. +, La. +, Mass. +, Md. +, Maine +, Mich. +, Minn. +, Mo. +, Miss. +, Mont. +, N.C. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, Ohio +, Pa. +, Puerto Rico +, S.C. +, Tenn. +, Tex. +, Utah +, Virgin Islands +, Vt. +, Wis. +, W.Va. +, Wyo. +, Ont. +, Que. +, Fla. +, Nebr. +, Ariz. +  and Nev. +
capillary +
sometimes longer +
concealing +
2 +  and 1 +
compressed +  and terete +
5-14(28)-veined +
collapsed and embedded in the rachis +  and shallow +
stiff +  and flexible +
shorter or longer +
subtending +
reduced +
membranous +  and chartaceous +
uncinate +
staminate +, unbranched +, pedunculate +  and pistillate +
distichous +  and paniculate +
pedunculate +  and multiple-stalked +
4cm +  and 30cm +
bisexual +  and unisexual +
1cm +  and 10cm +
solid +  and hollow +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.82 cm8.2 mm <br />0.0082 m <br />) +
not disarticulating +
distichous +  and more or less polystichous +
photosynthetic +
not aromatic +
coriaceous +
membranous +
inconspicuous +
complex +  and simple +
concealed +  and prominent +
sessile-pedicellate +  and subsessile +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
fused +  and free +
dry +  and fleshy +
elongate +
8 (?) +  and 24 (?) +
bladeless +  and open +
pedunculate +  and pistillate +
polystichous +
4 cm40 mm <br />0.04 m <br /> (?) +  and 30 cm300 mm <br />0.3 m <br /> (?) +
1 cm10 mm <br />0.01 m <br /> (?) +  and 10 cm100 mm <br />0.1 m <br /> (?) +
staminate +, sessile +, pistillate +, disarticulating +  and pedicellate +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
sterile +  and bisexual +
usually smaller +  and reduced +
2.5mm +  and 5mm +
1 (?) +  and 3 (?) +
fused +  and free +
filamentous +
dome--shaped +  and triangular +
Gramineae +
exposed +  and concealed +
Zea mays +
species +
membranous +
sessile-pedicellate +
aquatic +  and terrestrial +