Centaurea solstitialis, L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 284

157. C. solstitialis L. , Sp. Pl. 917 (1753).

Biennial. Stems 30-100 cm, erect, much branched from lower half, usually greyish-tomentose; branches long, winged. Leaves scabrid, and arachnoid or lanate, or greyish-tomentose; lower usually lyrate to pinnatifid, with triangular-oblong lobes; upper linear-lanceolate, entire, mucronate. Capitula solitary. Involucre 7—12(—15) mm in diameter, usually ovoid-globose; bracts broadly ovate; appendages not decurrent, short, the apical spine 10—15(—30) mm, with basal spines c. 3 mm. Florets usually yellow, eglandular, uniform. Achenes c. 2-5 mm, black; pappus up to 5 mm. 2л = 16. Dry, open habitats. S. Europe; a frequent casual elsewhere and naturalized in parts of C. Europe. Al BI Bu Co Cr Ga Gr Hs It Ju *Rm Rs (*W, K) Sa Si Tu [Au Br Cz Ge He *Hu Po].

1 Appendages with stout apical spine and 1-2 short lateral spines

2 Upper leaves linear-lanceolate; appendages with yellow apical spine (c) subsp. schouwii

2 Upper leaves linear; appendages with reddish-brown apical spine (d) subsp. erythracantha

1 Appendages with 3-7 spines

3 Spines yellowish, the apical stouter and much longer than the others (a) subsp. solstitialis

3 Spinesbrownish,subequalortheapicalslightlystouter and longer (b) subsp. adamii