Vascular Plants of North Carolina
Account for Black Knapweed - Centaurea nigra   L.
Members of Asteraceae:
Members of Centaurea with account distribution info or public map:
Google Images
Section 6 » Order Asterales » Family Asteraceae
Show/Hide Synonym
DistributionCollections are known from only 2 counties: Forsyth in 1919 and Haywood in 1936 and 1938. However, the Haywood plants clearly have showy ray florets (herbarium DUKE), and so they are C. nigrescens. The Forsyth collection appears to be correctly identified: Crafton Heights, Winston-Salem, 1919, P.O. Schallert (DUKE).

Native of Europe; in N.A. Newf. to Ont. and WI, south to NC, KY, and MO; also northwestern states.
AbundanceVery rare.
HabitatNo NC data.
PhenologyFlowering and fruiting July-October.
IdentificationBlack Knapweed can be told from most others in the genus by its black, deeply fringed appendages that generally obscure the phyllaries (bracts surrounding the base of a head). It also lacks ray florets, and thus looks more like a typical thistle (Cirsium). Centaurea nigrescens has showy ray florets and the phyllary bodies are not obscured by black appendages.
Taxonomic Comments
Other Common Name(s)
State RankSE
Global RankGNR
State Status
US Status
County Map - click on a county to view source of record.
Photo Gallery
B.A. SorrieField, Newport, RI, 1971. Photo_non_NCPhoto_non_NC
Select a source
Select an occurrence type