Cardo de leche (Guía de malezas invasoras de Cambria (Invasive Weeds of Cambria)) · iNaturalist

milk thistle (Guide to Cambria's Invasive Weeds) · iNaturalist

Algarrobo Blanco/ The Argentine Mesquite /Prosopis Alba

Russian thistle (Plants of the Middle Rio Grande Bosque) · iNaturalist

cardo mariano (Malezas Urbanas de Duitama) · iNaturalist

Photos of Rusby's milkweed (Asclepias rusbyi) · iNaturalist

Artichoke Thistle (Invasive Plants in John Muir National Historic Site) · iNaturalist

Cardo italiano (Guía de malezas invasoras de Cambria (Invasive Weeds of Cambria)) · iNaturalist

Photos of slimleaf milkweed (Asclepias stenophylla) · iNaturalist

Genus Rissoina · iNaturalist

Common Milkweed (Plants of the Peggy Notebaert Nature Museum Grounds, Chicago, Illinois) · iNaturalist

Photos of Rusby's milkweed (Asclepias rusbyi) · iNaturalist

Photos of Zizotes milkweed (Asclepias oenotheroides) · iNaturalist