Dittrichia viscosa subsp. viscosa

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 : 137

(a) Subsp. viscosa :

Stems erect; leaves 30-60 x 4-30 mm, oblong-lanceolate; margin flat. Throughout the range of the species, except S. W. Portugal.