T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Centaurea calcitrapa (Star thistle)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Asterales
Family: Asteraceae
Tribe: Cynareae
Genus: Centaurea
Species: C. calcitrapa
Binomial name: Centaurea calcitrapa
Common name: Star thistle, Red star-thistle.

Centaurea calcitrapa is an annual or biennial species of flowering plant native to southern and western Europe. It has been introduced to New Zealand. This noxious weed is found in Northland, East Cape, King Country, Hawkes Bay Marlborough, Canterbury, Otago and the Chatham Islands. It habitat is roadsides, waste places and pastures.
Centaurea calcitrapa starts life as a tap rooted rosette. During November and March it produces an erect, branched and hairy flower stem up to 1.3 m tall. The lowermost leaves may reach a length of 20 centimetres and are deeply lobed. Between November and April it produces pink-purple, 8 mm in diameter flower heads that have vicious spines around them.