The yellow plumed thistle (Picnomon acarna) belongs to Asteraceae (the Aster family). It is an annual herb that is native to southern Europe and south-western Asia. This herb grows in agricultural areas, in waste areas and roadsides, and it can reach up to 100 cm in height. It forms a basal rosette of leaves during the early stages of growth. The basal leaves are slightly lobed, with distinct short yellow spines, and grow to 30 cm long. The stem leaves are long and narrow with long yellow coloured spines on their teeth or lobes. The stems are many branched and have spiny wings that extend downwards from the base of the leaves and dense cobweb. The pink or purple flower-heads bloom in summer. They consist of numerous florets surrounded by several layers of bracts that are tipped with sharp, multi-forked, yellow spines.