Centaurea ×moncktonii
C.E.Britton Meadow KnapweedAscending, rhizomatous perennial to 1.5 m high. Basal leaves oblanceolate or elliptic, to 25 cm long, 4 cm wide, entire to pinnatifid, acute, surfaces pubescent to scabrous, petiolate; cauline leaves linear to lanceolate, 1–8 cm long, 2–10 mm wide, entire or sparsely toothed, acute, sessile. Capitula solitary, broad ovoid, 15–18 mm diam.; involucre 12–18 mm long; intermediate involucral bracts ovate to lanceolate, tomentose to glabrous, with a light to dark brown, pectinate, terminal appendage 4–5 mm long; inner involucral bracts longer with lacerate terminal appendages. Corolla 15–20 mm long, purple (rarely white in overseas material). Cypselas 2.5–3 mm long, pale brown or grey, obscurely ribbed; pappus of bristles c. 1 mm long or absent. Flowers late spring to autumn.
GipP, HSF, HNF, Strz. Also naturalised SA, Tas. Known in Victoria from the Dandenong Ranges and the Latrobe Valley, Gippsland, where found on roadsides and other disturbed sites.
Centaurea ×moncktonii is suspected of being a naturally occurring hybrid between C. jacea and C. nigra.