Great Starthistle - Centaurea scabiosa
Other Names:
Greater Knapweed
Perennial. Stems erect, branched, 30–100 cm. Herbage glabrate. Leaves petiolate; blades lanceolate to ovate, 5–25 cm long, pinnately lobed, more deeply so above. Inflorescence with few heads. Involucres broadly campanulate, 12–25 mm high; phyllaries green with dark, scarious, pectinately branched appendages at the tip; the outer ovate; inner oblanceolate. Disk flowers numerous, rose-purple; the outer enlarged; inner corollas 20–25 mm long. Achenes 4–5 mm long, puberulent; pappus of numerous bristles (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
POLLINATORS The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap:
Bombus vagans,
Bombus bifarius,
Bombus centralis,
Bombus fervidus,
Bombus rufocinctus,
Bombus ternarius,
Bombus terricola,
Bombus occidentalis,
Bombus griseocollis,
Bombus impatiens,
Bombus insularis, and
Bombus suckleyi (Thorp et al. 1983, Johnson 1986, Colla and Dumesh 2010, Koch et al. 2012, Williams et al. 2014, Tripoldi and Szalanski 2015).