Centaurea diluta

Annuals or perennials, to 200 cm. Stems simple proximally, openly branched distally, glabrous or thinly hairy. Leaves thinly pubescent, basal and proximal cauline petiolate, blades 10-15 cm, margins coarsely pinnately lobed; mid cauline sessile or short-petiolate, short-decurrent, blades obovate or narrowly oblong, 2-8 cm, entire to pinnately lobed; distal cauline oblong, entire to irregularly lobed. Heads radiant, in open cymiform arrays, pedunculate. Involucres ovoid, 8-15 mm diam. Principal phyllaries: bodies greenish, ovate, scarious-margined, appendages stramineous to brown, scarious, fringed with slender teeth, tipped by slender spines 1-5 mm. Innermost phyllaries unarmed with brown, expanded, lacerate appendages. Florets many; corollas pink-purple, those of sterile florets 25-30 mm, enlarged, raylike, those of fertile florets ± 20 mm. Cypselae tan, 3-3.5 mm; pappi many. white, unequal bristles 3-5 mm. 2n = 20.

Flowering spring (Apr-Jun). Escaped from cultivation in disturbed sites; 0-100 m; introduced; Calif., Mo., N.Y.; sw Europe; n Africa.