Calystegia sepium subsp. sepium

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 78

(a) Subsp. sepium :

Glabrous. Leaves variable; sinus acute. Bracteoles usually 10-15 mm wide. Corolla usually 30-50 mm, white or rarely pale pink. Stamens (15—)17—23(—25) mm; anthers 4-6 mm. 2« = 22. River- and lake-margins, marshes, hedges and waste places. Almost throughout the range o f the species.