Involucre - To 1.2cm tall(long), 7-8mm in diameter, ovoid to slightly urcreolate in shape. Phyllaries with prickle tips, imbricate, with some arachnoid pubescence, dark brown to black in upper half, green in lower half. Margins pectinate.
Ray flowers - Absent.
Disk flowers - Outermost flowers enlarged, sterile, 5-lobed. Lobes to 8mm long. Innermost flowers 5-lobed, whitish to pinkish, fertile. Lobes to 4mm long. Anthers pinkish-rose 2-3mm long.
Flowering - June - August.
Lucas Land
Spotted Knapweed
Centaurea stoebe
Photos by Phil Lucas
From Missouri Plants
Stems - To 1.5m tall, erect to reclining with age, herbaceous, branching, multiple from base, from taproot, slightly scabrous, striate.
Leaves - Main cauline leaves alternate, deeply pinnatifid, (many lobes divided again), to +/-12cm long, +/-7cm broad. Leaves in upper portions of stem greatly reduced, mostly undivided, scabrous, typically arachnoid pubescent, mucronate, linear to oblong.
Inflorescence - Single flower head terminating stem in a loose paniculiform arrangement of the upper 1/2 of stems.
