Purple Starthistle

Centaurea calcitrapa

Pinkish flower subtended by bracts with long spines.

a clump of starthistle with thin leaves.

Plant Description

A biennial or perennial bushy thistle with finely hairy stems and leaves and purple to pink thistle-like blooms and bracts tipped with long straw colored spines. Its basal rosette with deeply divided leaves and a central cluster of spines.

Plant Details

Life Forms	Forb
Habitats	Floodplains & Wet Meadows Forests & Woodlands Grasslands & Oak Savannas
ODA Listing	A
Soil and Moisture Conditions	Moist
Suggested Actions	Report to Oregon Invasives Hotline
Shade Preference	Full sun
Mature Height	2-3'
Distribution	Found extensively in California and in a few counties in Oregon and Washington.
Control	If you find this plant, report it to OregonInvasivesHotline.org.
Reproduction and Spread	Reproduces by seeds which are dispersed by the movement of vehicles, equipment, soil, apparel, and animals.
Introduced	Native to southern Europe, introduced to California in the early 1900s.
Look Alikes	Other Centaurea species (knapweeds and starthistles)
Impact	Invades pastures, Meadows, and fields and displaces desirable forage plants. Unpalable so it increases as palatble plants are consumed. Creates impenetrable stands.
More Info	https://www.invasiveplantatlas.org/subject.html?sub=5268