This is a succulent perennial which grows in rocky places, salt marshes, shingle and cliffs. At times reaching 1m high, it is an erect plant with bright green, linear leaves which crowd up along the stem. At the top of this stem is a loose, flattish cluster of yellow daisy-like flowers, (15-30mm) each with spreading rays surrounding a centre of disc florets. They bloom in July and August. The overlapping bracts behind the rays are green, linear and erect. This is a native plant and is not related to Rock Samphire. It belongs to the family Asteraceae.
My first record of this plant was in 2003 when I found it by the cliffs at Killiney Bay, Co Dublin where I photographed it.
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre