Rubus, P. J. Mueller

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 : 10

Subsect. Suberecti P. J. Mueller . Stems usually suberect, glabrous, often suckering from the base and rarely rooting apically, often angled; prickles subequal; stalked glands usually absent. Leaves usually more or less green beneath. Inflorescence usually a raceme or corymb. Sepals green externally, often with white margin; petals often hairy. Fruit black or reddish-black. Flowering early.