Synonym:  Centaurea biebersteinii  DC.
    
Synonym:  Centaurea maculosa  Lam.  ssp.  micranthos  Gugler

              
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Plants of fields, roadsides, open disturbed areas.  Flowers July to September.  Not native.  Invasive.  Our plants are: 

[ Centaurea stoebe L. ssp. micranthos (Gugler) Hayek ]     

Perennial.  Stems are 1 or more per plant; sparsely to somewhat more densely pubescent with matted or cobwebby hairs; often branching from below midstem.  Typical height is 2 to 3+ feet.

The overall inflorescence is open, with numerous widely spreading to ascending branches, each branch bearing a small number of flower heads, clustered toward branch tips.

Flower heads are pseudo-radiateInvolucres are flask-shaped, 10-13 mm high.  Florets are 30-40.  Peripheral florets are enlarged (relative to inner florets), neuter, 5-lobed, falsely appearing as rays, usually pink/magenta.  Central florets are bisexual and fertile; smaller than peripheral florets, corollas pink or white, tubular, apically with 5 slender, spreading lobesAppendages of involucral bracts are dry, thin, triangular in shape, dark brown to black, with comb-shaped fringes along the edges, not obscuring the bodies of the adjacent involucral bracts.

Basal leaves are usually not present at flowering.  Stem leaves are oblanceolate to linear, the larger ones deeply divided into linear segments and often also irregularly lobed.

Cypselae are obovoid, truncated at the summit, pale, brown-striped.  The pappus is of minute, whitish bristles.

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Selected references:  Keil and Ochsmann (2006)Haines (2011).

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Similar species:  other species in the genus Centaurea.

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