Centaurea ruthenica, Lam.

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 : 263

5. C. ruthenica Lam. , op. cit. 663 (1785).

Stems 100-150 cm, from a woody rhizome, simple or sparingly branched above, lanate at the nodes below, glabrous above. Leaves 20-25 x 10-13 cm, deep green, glabrous, ovate-oblong in outline; lower pinnatipartite, long-petiolate; upper pinnate, with linear-lanceolate segments, serrate from base to apex, broadly decurrent. Involucre 10-20 mm in diameter, cylindrical-ovoid; bracts obscurely striate, the middle oblong, without or with scarious margin c. 0-5 mm wide near apex, the inner linear, with orbicular appendage. Florets pale yellow. Pappus shorter than to as long as achene. Steppes and stony grassland. S. part of U.S.S.R., extending locally westwards to C. Romania. Rm Rs (C, W, E).

Very variable; 6-8 perhaps may prove to be subspecies of 5 upon further investigation.