Chenopodium urbicum is similar to Chenopodium macrospermum (rare casual). - Sometimes mixed up with Chenopodium chenopodioides (4), Chenopodium murale (9), Atriplex prostrata and Atriplex hortensis . The species of Atriplex can be distinguished even in the vegetative phase by (sub)opposite branches and leaves.
Habitat. Very nitrophilous, but a poor competitor. Nitrogen-rich places in farmland (dungheaps, cowhouses and farmyards), in the 18th and 19th centuries also town streets; in the later part of the 20th century mainly as a casual (railway yards, ports, fields and grain mills). The disappearance is probably mainly due to improved sanitary conditions.
A. I.C. Hedge, H. Akhani, H. Freitag, G. Kothe-Heinrich, D. Podlech, S. Rilke & Pertti Johannes Uotila 1997: Chenopodiaceae: p.36, B. Paul Mouterde 1966: Nouvelle Flore du Liban et de la Syrie, C. Wolfgang Adler & Alexander Ch. Mrkvicka 2003: Die Flora Wiens, gestern und heute: p.154, D. Jacques Lambinon & Filip Verloove 2012: Nouvelle Flore de la Belgique, du G-.D. de Luxembourg, du nord de la France et des Régions voisines, 6th: p.160, E. Daniel Jeanmonod & Jacques Gamisans 2007: Flora Corsica: p.327, F. Marie Zajac, Adam Zajac & Bogdan Zemanek 2006: Flora Cracoviensis Secunda: p.66
Europe (especially the SE part); from SW Asia to Siberia; also North America (not native).
Distribution. Archaeophytic at least in parts of F and S (but now extinct); also a casual alien, in D and N perhaps never established. - D ØJy Vejle 1930, 1932, 1999, FyL Svendborg 1905; Sjce København 1985, Farum 1990-97 (with compost from the botanic garden in København); a few records from Sjæ, LFM and Brn in the period 1825-1939. N 0/Halden 1827, Ak Oslo and Bærum (both before 1900), Ho Etne 1959 (poultry farm). S formerly scattered to rare north to Vrm, Vsm and Gst and fairly abundant in some towns (e.g. Gtl Visby, Upl Uppsala), nowadays disappeared, last seen as established in Vsm Bro 1987; casual north to Mpd and in Nb\ most recently recorded, as a casual, in Bl Ramdala 1989, Kim Torsås 1999, Smi Tingsås 1999, 2000, BhG Göteborg 1993 and Nb Nederkalix 1997. F in the 19th century apparently ± established as an archaeophyte or a relatively old alien in some old towns and villages (at leasts Finström, Saltvik, Sund, Kumlinge, V Korppoo, Särkisalo, U Inkoo, Helsinki, Porvoo, Myrskylä, EK Kotka and EH Sysmä), now disappeared; casual occurrences, most often of Russian origin, after 1950 at least in U Helsinki 1950's to 1960's, EH Nokia 1972 (tip), Tampere 1961, 1963 (railway yard), 1976 (mill), ES Savonlinna 1950's (tip), EP Vaasa 1950's (docks), PK Värtsilä 1990 (railway yard) and OP Oulu 1960 (docks).
Therophyte (summer-annual). 10-60(-100) cm, glabrous or sometimes farinose, olive-green or sometimes brownish. Stem angular, yellowish, never red in the leaf axils, hard, erect, sparsely branched. Lower and middle leaves with petiole less than half as long as the blade; blade fairly thick, ± broadly triangular, sometimes as wide as long, often with outward-pointing basal lobes, 3-10(-18) x 3-8(-20) cm; base ± truncate (slightly cuneate to slightly cordate); apex obtuse or sometimes acute; margin sinuate to dentate with teeth pointing outwards or sometimes recurved, or rarely subentire; teeth at the widest point of the blade larger than the others. Upper leaves with narrowly triangular to trullate or lanceolate blade. Inflorescences axillary and terminal, erect, spikelike, ebracteate; glomerules very small, dense. Flowers monomorphic, bisexual or female. Tepals 5, connate at base, not keeled, with wide membranous margin; apex obtuse. Stamens 5. Stigmas 2 or sometimes 3, 0.1 mm. Nut falling with or without the perianth; pericarp not or weakly adherent to the seed. Seed horizontal, orbicular in outline, 1-1.2 mm; edge rounded; seed-coat black, glossy, almost smooth to obscurely reticulate or rugulose. - Mid-summer to early autumn. [2n=36]
Variation. Variants based on differences in leaf shape have sometimes been recognized. Nordic plants have broadly triangular leaf-blades and seem to match
Chenopodium urbicum var. urbicum fairly well.