Centaurea jacea nothosubsp. pratensis
Family: Asteraceae · Type: Perennial · Not Native
Conservation status: Cal-IPC Yes
Centaurea jacea nothosubsp. pratensis is a non-native California perennial in the Asteraceae family, recognized by brown scarious appendages and variable head type distinguish from other knapweeds.
meadow knapweed is a naturalized perennial found in northern coastal ranges and cascade ranges in grasslands, disturbed places, and montane forests at elevations of 150 to 1,100 meters. Flowering from August to October, this plant produces pale flower heads with radiant disk flowers up to 22 millimeters long. Growing with erect stems, it forms dense clusters in open areas. Its flower heads have distinctive phyllary tips with light to dark brown appendages that are coarsely dentate or dissected into fine, wire-like lobes. The plant spreads readily in disturbed habitats, with white or tan pappus scales developing on its fruits.
Identification and appearance
Key characters: 11 sympatric species; brown scarious appendages and variable head type distinguish from other knapweeds
Habitat and range
Habitat: Grassland, disturbed places, montane forest
Elevation: 150-1100 m
Outside California: to southern Canada, eastern United States, native to Europe or locally derived from hybridization of parental taxa native to Europe
Bloom period
Centaurea jacea nothosubsp. pratensis blooms Aug-Oct.
Conservation status
Cal-IPC Yes
How to tell it apart
vs Cirsium: Cirsium bracts taper to simple spines; Centaurea bract tips expanded with fringed/toothed edges; vs Carduus: Carduus bracts spine-tipped but not fringed; Centaurea bract appendages distinctly fringed or toothed; vs Jacobaea: Jacobaea has obvious yellow ray flowers; Centaurea lacks true rays (all tubular flowers); vs Silybum: Silybum has white-veined leaves and simple spine-tipped bracts; Centaurea bracts ornately fringed; vs Eriophorum: Eriophorum is a sedge with grass-like leaves and cottony heads; Centaurea is a branched herb
Frequently asked questions
Is Centaurea jacea nothosubsp. pratensis native to California?
No. Centaurea jacea nothosubsp. pratensis is not native to California (recorded as not native).
When does Centaurea jacea nothosubsp. pratensis bloom?
Centaurea jacea nothosubsp. pratensis blooms Aug-Oct.
What plant family does Centaurea jacea nothosubsp. pratensis belong to?
Centaurea jacea nothosubsp. pratensis is in the Asteraceae family, genus Centaurea.
Is Centaurea jacea nothosubsp. pratensis invasive in California?
Centaurea jacea nothosubsp. pratensis is listed by Cal-IPC with an invasiveness rating of Yes.
What habitat does Centaurea jacea nothosubsp. pratensis grow in?
Centaurea jacea nothosubsp. pratensis grows in Grassland, disturbed places, montane forest.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.