Trifolium ochroleucon, Hudson

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 171

85. T. ochroleucon Hudson , FZ. Angl. 283 (1762)

(incl. T. caucasicum Tausch , T. pallidulum Jordan ).

Shortly rhizomatous or caespitose perennial; stems 20-50 cm, ascending; upper internodes long. Leaflets 15-3O(-5O) x 5-8 mm, oblong-elliptical or lanceolate. Stipules with a linear-lanceolate, herbaceous apex. Heads 20-40 mm, globose or oblong, shortly pedunculate or subsessile. The 4 upper calyx-teeth equalling or shorter than the tube, the lowest usually longer and deflexed in fruit, with one distinct central vein, rarely with two lateral veins. Corolla 15-20 mm, exceeding the calyx, at first yellowish-white, rarely pink, ultimately falling. Legume thickened at the apex. Mainly in shady or somewhat damp habitats. W., C. & S. Europe. Al Au Be Br Bu Co Cz Ga Ge G r He Hs Hu It Ju Lu Po Rm Rs (W) Sa Si Tu.

Variable in indumentum, petal-colour and length of the calyxteeth, especially the lowest. Plants from S. Europe ( var. roseum (C. Presi) Guss. ) often have pink petals and the lowest calyxtooth 2-3 times as long as the tube, sometimes with two indistinct lateral veins; some plants from Ukraine and S. Russia have yellowish-white petals and 2 distinct lateral veins on the lowest calyx-tooth, the latter twice as long as the tube ( T. caucasicum Tausch ).