Argemone mexicana

A species found in both Mexico (as the name would suggest) and most of the eastern United States. My photographs are from Mexico, as Barranca de Batopilas. Flowers can apparently have either 3 or 6 petals; the plants I saw all had 3, as shown below.

A flower at Barranca de Batopilas, 22 Mar 2007.

Buds at Barranca de Batopilas, 22 Mar 2007.

Cauline leaves at Barranca de Batopilas, 22 Mar 2007.

Plant habit, Barranca de Batopilas, 22 Mar 2007.