A Mediterranean sp., has been collected on railroad ballast in Va., but may not be fully naturalized. The heads avg smaller than in no. 2 [Anthemis arvensis L.], the lvs are glandular-punctate beneath, and the achenes are tuberculate.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.