Chenopodium polyspermum

Linnaeus

Sp. Pl. 1: 220. 1753.

WeedyIntroduced
Treatment appears in FNA Volume 4. Treatment on page 286. Mentioned on page 276.

Stems erect or decumbent, branched, 1.5–5 (–10) dm, glabrous. Leaves nonaromatic; petiole to 1.7 cm; blade ovate to elliptic or oblong, 1.5–4 (–8) × 0.4–2.5 cm, base rounded to cuneate, apex obtuse to rounded or acute, glabrous. Inflorescences lateral cymes, sometimes terminal and axillary spikelike panicles; bracts absent or leaflike and gradually reduced in size distally. Flowers: perianth segments 5, distinct nearly to base, lobes elliptic to oblong, 0.7–1 × 0.5–0.8 mm, apex obtuse or rounded, not keeled, glabrous, not covering fruit at maturity; stamen 1; stigmas 2, 0.1 mm. Utricles depressed-ovoid; pericarp nonadherent, smooth. Seeds 0.8–1.3 mm diam.; seed-coat brown-black, dull. 2n = 18.

Distribution

V4 531-distribution-map.gif

N.B., Ont., Que., Sask., Maine, Mass., Mich., N.J., N.Y., Oreg., Pa., Wis., Europe, n Asia

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Key

1 Plants spreading to suberect; inflorescences lax, cymose, axillary; leaf blade apices usually obtuse, green or yellowish green. Chenopodium polyspermum var. polyspermum
1 Plants upright; inflorescences condensed, spiciform, terminal and axillary; leaf blade apices usually acute, becoming red at maturity Chenopodium polyspermum var. acutifolium

"narrower" is not a number."thin" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Chenopodium polyspermum"
dehiscent +  and indehiscent +
Steven E. Clemants +  and Sergei L. Mosyakin +
Linnaeus +
slippery +
aromatic +
rounded +  and cuneate +
Polysperma +
4 cm40 mm <br />0.04 m <br /> (8 cm80 mm <br />0.08 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
ovate +  and elliptic or oblong +
0.4cm;2.5cm +
persistent +  and deciduous +
reduced +
reddish-brown +, black +, brown +  and green +
N.B. +, Ont. +, Que. +, Sask. +, Maine +, Mass. +, Mich. +, N.J. +, N.Y. +, Oreg. +, Pa. +, Wis. +, Europe +  and n Asia +
hippocrepiform +  and annular +
symmetric +, or +  and uniseriate +
dehiscent +  and indehiscent +
small white +
inflated +
sessile +  and petiolate +
nonaromatic +
not fleshy +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
elliptic +  and oblong +
0.5mm;0.8mm +
not winged +  and winged +
acute +  and rounded +
crassinucellate +  and bitegmic +
campylotropous +
1 +  and single +
spikelike +
persistent +  and deciduous +
nonadherent +
chartaceous +  and membranaceous +
0 cm0 mm <br />0 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
pointing +  and ascending +
bulbous +  and taprooted +
fusiform +
fleshy +  and fibrous +
honeycombed +  and smooth +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (?) +  and 0.13 cm1.3 mm <br />0.0013 m <br /> (?) +
lenticular +  and subglobose +
Weedy +  and Introduced +
compound +, dense +  and loose +
cylindric +
not imbricate +
keeled +  and rounded +
opposite +  and alternate +
decumbent +  and erect +
not fleshy +
filiform +
0.1 cm1 mm <br />0.001 m <br /> (?) +  and 2 cm20 mm <br />0.02 m <br /> (?) +
sessile +  and petiolate +
reduced;small +
horizontal +  and vertical +
verrucate +
Chenopodium polyspermum +
Chenopodium subsect. Polysperma +
species +
dehiscent +  and indehiscent +
depressed-ovoid +
glabrous +  and pubescent +
polygamous +, dioecious +  and monoecious +
not imbricate +
keeled +  and rounded +