This is a very tall (to 2m) bristly, patch-forming wildflower frequently found throughout Ireland on roadsides, ditches, fields, coastal cliffs and beaches. It flowers from July to October and is one of the most attractive of the Sowthistles. Rich yellow flower-heads (4-5cm across) are held in loose clusters on slender stalks, which when broken exude a milky sap. The florets are all rayed and behind these are sticky, pointed bracts. The dark-green, narrow, alternate, shiny leaves have softly spiny margins, the middle and upper leaves clasping the stems with round lobes. The lower leaves are stalked and all the leaves are greyish below. Reproduction is by both seed – dispersed by white pappus – and widely spreading roots. New plants are able to establish themselves from very small pieces of these roots and this plant is commonly regarded as a 'weed'. It is a native plant belonging to the Asteraceae family.
My first record of this plant is in Ballitore, Co Kildare in 2003 and I photographed it on that occasion.
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre