1. Cota tinctoria (Linnaeus) J. Gay ex Gussone, Fl. Sicul. Syn. 2: 867. 1845.
Golden marguerite, yellow chamomile
Anthemis tinctoria Linnaeus, Sp. Pl. 2: 896. 1753
Leaves 1–3(–5) cm, ultimate lobes narrowly oblong to spatulate or linear, ultimate margins entire or serrate (teeth apiculate). Phyl-laries: abaxial faces sericeous to arachnose, margins often ciliolate. Paleae 4–5 mm (including spinose tips). Ray laminae yellow, 6–12+ mm. Disc corollas 3.5–4 mm. Cypselae 1.8–2.2 mm; pappi usually 2–2.5 mm. 2n = 18.
Flowering Jul–Sep. Disturbed sites, fields, roadsides; 10–600+ m; introduced; Alta., B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Que., Sask.; Alaska, Ark., Calif., Conn., Idaho, Ill., Iowa, Maine, Md., Mass., Mich., Minn., Mo., N.H., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., R.I., S.Dak., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Europe, Asia.