Calendula arvensis L.
field marigold
Erect or sprawling annual herb, up to c. 30 cm tall. Stems densely clothed in short, erect, eglandular and glandular hairs, less hairy below, much- branched. Basal and lower cauline lvs moderately to densely clothed in simple and glandular hairs, ciliate, obovate to obovate-oblong, with few scattered marginal teeth, acute and mucronate, apetiolate and slightly cuneate, 2-8 × 0.5-1.5 cm; upper cauline lvs similar to lower but becoming smaller, oblong, lanceolate, or narrowly ovate-triangular, broad-based and often ± amplexicaul. Capitula solitary, 10-15 mm diam. Involucral bracts in 2 rows, hairy, glandular and ciliate, narrowly ovate- to oblong-triangular, acuminate, 6-9 mm long, the inner with more conspicuous membranous margins. Ray florets c. 11-22, in 1-2 rows; ligules yellow or orange, ± = or not greatly exceeding bracts, c. 5-10 mm long. Disc florets few, yellow or orange. Achenes glabrous to moderately hairy, usually of 3 types; outermost achenes incurved, short-beaked, 7-10 mm long, with small stout spines on back; some outer achenes slightly shorter, scarcely beaked, broadly 2-3-winged and usually tuberculate on back; inner achenes enclosed by outer, ridged or tuberculate on back, 2-4 mm diam.
N.: known from one area only, vicinity of Napier.
S. Europe, Mediterranean, E. to Caucasia, Iran and Afghanistan 1984
Coastal waste places along road and railway, locally common.
FL Oct-Jul.
According to European Floras more vigorous specimens may have lvs up to 2 cm across, and ligules up to 18 mm long, and so approach C. officinalis; however, C. arvensis is generally smaller in all its parts and is easily distinguished by the small, few-rayed heads.
