Large spiny perennial to 2.5 m tall. Artichoke thistle primarily invades disturbed grasslands, especially those in coastal regions.
Dense colonies displace desirable vegetation and wildlife and can exclude livestock.
The two species readily hybridize, and a few spiny wild types often develop among globe artichoke seedlings. See Comparison of spiny-leaved thistles . Artichoke thistle was introduced from the Mediterranean region as a vegetable and ornamental. At publication time, the fly's impact on artichoke thistle populations is unknown. Larvae feed only on mature flower heads, thus commercial artichokes are not significantly affected.