On waste ground, damp places, roadsides (and my very own garden) this plant is a perennial which flowers from March to August. Growing to about 80cm high, it is a stiff, upright plant with strong, ridged stalks and it has yellow 4-petalled flowers (5-6mm across) which are borne in clustered terminal heads. The leaves are shiny, dark green and they are all lobed. The fruits are long, narrow 4-sided pods. This is not a native plant but is said to have been introduced from the Mediterranean, and it belongs to the family Brassicaceae.
I found this plant growing in Gibletstown, Co Wexford in 2009 and photographed it at that time. I hope to photograph it later when the seedpods have grown to help with identification.
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre