Dysphania ambrosioides

Plants annual. Stems erect to ascending, much-branched, 3–10(–15) dm, ± glandular-pubescent. Leaves aromatic, distal leaves sessile; petiole to 18 mm; blade ovate to oblong-lanceolate or lanceolate, proximal ones mostly lanceolate, 2–8(–12) × 0.5–4(–5.5) cm, base cuneate, margins entire, dentate, or laciniate, apex obtuse to attenuate, copiously gland-dotted (rarely glabrous). Inflorescences lateral spikes, 3–7 cm; glomerules globose, 1.5–2.3 mm diam.; bracts leaflike, lanceolate, oblanceolate, spatulate, or linear, 0.3–2.5 cm, apex obtuse, acute, or attenuate. Flowers: perianth segments 4–5, connate for ca. 1/2 their length, distinct portion ovate, rounded abaxially, 0.7–1 mm, apex obtuse, glandular-pubescent, covering seed at maturity; stamens 4–5; stigmas 3. Achenes ovoid; pericarp nonadherent, rugose to smooth. Seeds horizontal or vertical, reddish brown, ovoid, 0.6–1 × 0.4–0.5 mm; seed coat rugose to smooth.

Phenology: Fruiting summer–fall.
Habitat: River bottoms, dry lake beds, flower beds, waste areas
Elevation: 0-700 m

Ont., Que., Ala., Ariz., Ark., Calif., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Miss., Mo., Nebr., N.H., N.J., N.Mex., N.Y., N.C., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., native to North America and South America, widely naturalized throughout the tropics and warm-temperate regions of the world.

Discussion

Southern populations of Dysphania ambrosioides are native while those populations in the northern part of the flora area are introduced.

Selected References

None.

Lower Taxa