Stems erect to sprawling, simple to much-branched, 1-30 dm, sparsely to densely farinose. Leaves nonaromatic; petiole 1-2.5 cm, shorter than blades or occasionally longer; blade ovate-lanceolate to rhombic-lanceolate or broadly oblong, 1-5.5(-12) × 0.5-3.8(-8) cm, base narrowly to broadly cuneate, margins sinuous-dentate to shallowly serrate or entire, apex acute to subobtuse, farinose abaxially. Inflorescences glomerules or occasionally 1-flowered peduncles in terminal and lateral compound spikes, 2-19 cm; glomerules subglobose, 3-4 mm diam.; bracts absent. Flowers: perianth segments 5, distinct nearly to base; lobes ovate, ca. 1 × 1.1 mm, apex obtuse, keeled, farinose, largely covering fruit at maturity; stamens 5; stigmas 2, 0.2-0.3 mm. Utricles depressed-ovoid; pericarp nonadherent, occasionally adherent, smooth to papillate. Seeds lenticular, margins round, 0.9-1.6 mm diam.; seed coat black, smooth, indistinctly granulate and/or radially grooved, or with faint reticulate-rugose ridges. 2n = 54. Fruiting late summer-fall. Disturbed soils in open habitats; 0-1400 m; introduced; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Nunavut, Ont., P.E.I., Que., Sask., Yukon; Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo; probably mostly native in Europe. Chenopodium album, one of the worst weeds and most widespread synanthropic plants on the Earth, in its broad circumscription is also among the most polymorphic plant species. It is a loosely arranged aggregate of still insufficiently understood races. Hundreds of segregate microspecies and infraspecific entities (including nomenclatural combinations) of the C. album aggregate have been described and/or recognized by various authors. Some authors have recognized numerous segregate intergrading species, while others have developed elaborate infraspecific hierarchies with numerous subspecies, varieties, forms, and even numerous subforms (e.g., B. Jüttersonke and K. Arlt 1989), or have combined both approaches. Neither approach has brought satisfactory and uncontroversial results.

Erect annual, much branched and to 1 m when well developed, the stems only seldom pigmented at the nodes, the lvs and infl often turning reddish late in the season; lvs generally ±white-mealy, rhombic-ovate to lanceolate, 3-10 cm, broadly cuneate at base, the larger (lower) ones mostly 1.5-2+ times as long as wide and almost always toothed; fls in dense glomerules, forming interrupted or continuous spikes that are grouped into a terminal paniculiform infl; cal ±white- mealy, its segments ±strongly carinate or cucullate, covering the fr, or sometimes looser and exposing the fr; style divided to the base, wholly deciduous; pericarp very thin and delicate, closely adherent to the seed and usually scarcely separable from it, smooth or only obscurely roughened when viewed at 10נor even 20׬ uniformly black or blackish; seeds horizontal, black, shining, mostly 1.0-1.5 mm wide, usually marked with a faint radial furrow, otherwise smooth or nearly so; 2n=54. June-Oct. Polymorphic European weed, now widely intr. in N. Amer. and elsewhere. Sometimes divided into an indefinite number of infraspecific taxa or specific segregates. (C. glaucophyllum; C. lanceolatum, a relatively narrow-lvd form) In our range the two following segregates are particularly noteworthy and probably merit some sort of taxonomic recognition.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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