Dioscorea polystachya

Turczaninow

Bull. Soc. Imp. Naturalistes Moscou 10(7): 158. 1837.

Common names: Cinnamon vine Chinese yam
IntroducedIllustrated
Synonyms: Dioscorea batatas Decaisne
Treatment appears in FNA Volume 26. Treatment on page 483. Mentioned on page 478, 480, 481.

Plants tuberous; tubers 1–many, on long stalks and deeply buried, spindle-shaped. Stems twining clockwise, unwinged, terete, climbing to 5 m, producing small bulbils (less than 2 cm diam.) in leaf-axils. Leaves alternate proximally, usually opposite distally, occasionally ternate, 3–9 × 3–11 cm; petiole as long as blade, base not clasping; blade 7 (–9) -veined, hastate-cordate, glabrous, margins 3-lobed, basal lobes spreading, rounded to ± rhombic, median lobe deltate to ovate, apex acuminate or mucronate; primary-veins 7 (–9); basal leaves often less distinctly lobed or entire and ovate-cordate. Staminate inflorescences axillary, in fascicle of (1–) 3–5 spikes, each spike shorter than 5 cm, or primary inflorescence axis elongate and bearing multiple fascicles; spikes bearing flowers singly, flowers bracteate, distributed along rachis in markedly zigzag pattern, internodes less than 2 mm. Pistillate inflorescences 1 per leaf-axil, few-flowered, shorter than 5 cm, internodes between mature flowers greater than 1 cm. Staminate flowers: perianth drying dark, tightly cupshaped; tepals ovate, ca. 1 mm, margins hyaline, apex acute; fertile stamens 6; filaments connate basally; anthers as long as or longer than filaments, thecae distinct, weakly spreading. Pistillate flowers: perianth as in staminate flowers; staminodes 6 in 2 subequal whorls, anthers and filaments more strongly differentiated in inner whorl, filaments less developed in outer whorl, all smaller than fertile stamens. Capsules not reflexed at maturity, broadly ovate, (1.2–) 1.7–2 cm wide. Seeds winged all around. 2n = 140.


Habitat: Staminate plants flowering summer. Thickets, ravines, stream banks, creek bottoms, limesinks, granite outcrops, alluvial woods, roadsides, drainage canals, waste places, fence rows
Elevation: 0–500 m

Distribution

V26 1004-distribution-map.jpg

Introduced; Ala., Ark., Conn., D.C., Fla., Ga., Ky., Md., Mass., Miss., Mo., N.J., N.C., Ohio, Pa., S.C., Tenn., Va., W.Va., e Asia

Discussion

Dioscorea polystachya is native to eastern Asia, where it is cultivated for its edible tubers. In North America, it is planted as a garden ornamental and has become naturalized throughout much of the eastern United States.

Only one pistillate specimen was encountered from the flora area, the plants apparently propagating vegetatively.

Dioscorea polystachya is the earliest published name for this species. The name D. oppositifolia Linnaeus, which has been misapplied to this species, actually refers to an ovate-leaved species that is native to the Indian Subcontinent and is not found in the flora area. For a more detailed nomenclatural history of D. polystachya, see Ting C. T. and M. G. Gilbert (2000).

Selected References

None.

Lower Taxa

None.

"wide" is not a number."-3timeslengthofperianth" is not declared as a valid unit of measurement for this property.

... more about "Dioscorea polystachya"
tetrasporangiate +
subequal +
acute;mucronate;acuminate +
Lauren Raz +
Turczaninow +
ovate-cordate +, entire +  and lobed +
rounded;more or less rhombic +
7(-9)-veined +
hastate-cordate +
Cinnamon vine +  and Chinese yam +
long-appendiculate +
bracteolate +
Ala. +, Ark. +, Conn. +, D.C. +, Fla. +, Ga. +, Ky. +, Md. +, Mass. +, Miss. +, Mo. +, N.J. +, N.C. +, Ohio +, Pa. +, S.C. +, Tenn. +, Va. +, W.Va. +  and e Asia +
0–500 m +
differentiated +
pistillate +, staminate +  and bracteate +
3-winged +  and capsular +
loculicidal +
perennating +
Staminate plants flowering summer. Thickets, ravines, stream banks, creek bottoms, limesinks, granite outcrops, alluvial woods, roadsides, drainage canals, waste places, fence rows +
grouped +  and paniculate +
few-flowered +, pistillate +  and staminate +
5 cm50 mm <br />0.05 m <br /> (?) +
cymose +, spicate +, unbranched +  and branched +
racemose +  and paniculate +
0 cm0 mm <br />0 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
opposite +  and alternate +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
3 cm30 mm <br />0.03 m <br /> (11 cm110 mm <br />0.11 m <br />) +
parietal +, axile +  and placentation +
cup-shaped +
Bull. Soc. Imp. Naturalistes Moscou +
compressed +
Introduced +  and Illustrated +
5 cm50 mm <br />0.05 m <br /> (?) +
persisting +, or +  and renewed +
climbing +  and twining +
sometimes +  and glabrous +
than for more a single growing season +
persistent +
distinct +
Dioscorea batatas +
Dioscorea polystachya +
Dioscorea +
species +
0.3 cm3 mm <br />0.003 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1 cm10 mm <br />0.01 m <br /> (?) +
distinct +
divided +
spindle--shaped +
subequal +
expanded +