Spiraea decumbens subsp. decumbens

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 : 5

(a) Subsp. decumbens :

Leaves acutely serrate, pale green and glabrous beneath. Pedicels and rhachis of inflorescence glabrous. 460-800 m. Mainly in the eastern part of the range.