Carduus crispus

The leaves of the Carduus crispus plant

The flowers of the Carduus crispus

The leaves of this plant are simple, alternate and they start at the base of the pant. The leaves cannot be in leaflets, but they can vary between being lobed and unlobed. The blade edges of the leaves can either be toothed, have lobes, or have both.[11] The top of the leaves does not have a lot of hair, while the bottom side of the leaves has white hair.[12] The size of the leaf blades vary from 10–20 cm in length, and the petioles are winged at the base of the leaves.[13]

Unlike most other members of the Asteraceae family, this plant does not have any ray-shaped flowers, only disk-shaped flowers, with the head width reaching 15 to 18 mm.[11] The colours of the flowers can range from purple to pink and white. The flowers are hermaphrodite, as they have both male and female parts.[13] In terms of pollination and reproduction, before the seeds get dispersed by wind dispersal, they require pollination by insects such as bees.[13][14]

The type of fruit this species produces is called achenes, and they are yellow or slightly gray and brown in colour.[15] The round-shaped fruit is flattened,[12] and attached to one end are long unbranched hairs[12][15] that aid with dispersing the seeds far and wide, with the help of winder dispersal.

The species and genus is a favorite food plant of caterpillars of the painted lady butterfly (Vanessa cardui), which derives its specific epithet, cardui, from their preference for Carduus thistles. It is also used by bees for honey production.

This plant has been found to have anti-tumour[16] properties, the active ingredient is Crispine B, an alkaloid that has cytotoxic properties, meaning that Crispine B is toxic enough to prevent cancer cells from replicating.[17]

The roots of C. crispus are said to have anodyne properties[18][19] which are pain-killing properties that lessen the pain an organism is experiencing.