Publication: Consp. Fl. Eur. 433. 1879.
Origin: Introduced from Europe
selected vouchers: WTU
Notes: Stace (1997) notes this may not be distinct from var. arvensis, and the vars. are not recognized in Jeps. Man., but they are provisionally accepted here, following Chambers and Sundberg (2000), and Douglas et al. (1998)