Some authors still place Cannabaceae in the Moraceae family (see for instance Nelson 1997) but this no longer is acceptable (Mabberley 2008). The family was traditionally placed in Urticales but molecular data demonstrated that Cannabaceae actually is embedded within the order Rosales (Sytsma & al. 2002).
Only a single species of the family is native in Belgium, Humulus lupulus L. (Lambinon & Verloove 2012). In addition to the two genera included in this account a third is worth mentioning, Celtis L. This genus was formerly included in Ulmaceae (or in a family of its own, Celtidaceae) but also belongs in Cannabaceae. At least two species are often planted as ornamental trees (European C. australis L. and American C. occidentalis L.) and both easily escape, especially the latter (e.g. Breunig 2010 for an overview). It should be looked for in Belgium as well. Celtis closely resembles Ulmus in leaf characters (often oblique bases, serrate margins, rough surfaces, etc.) but fruits are drupes (vs. samaras) and leaves are palmately veined at base (vs. pinnately veined throughout).

1 Erect annual. Leaves (at least the upper) alternate, palmately divided nearly to base into 5-9 lanceolate-elliptic lobes. Petioles without branched hairs === Cannabis 
Climbing perennial (rarely annual). All leaves opposite, divided at most ca. ¾ to base into 3-5 ovate lobes (sometimes unlobed). Petioles with branched hairs === Humulus


Breunig T. (2010) Der Westliche Zürgelbaum (Celtis occidentalis) in Südwestdeutschland und angrenzenden Gebieten. Neue Verbreitungskarten zur Flora Baden-Württembergs, Folge 7. Berichte der Botanischen Arbeitsgemeinschaft Südwestdeutschland 6: 69-78. [available online at:

Lambinon J. & Verloove F. (2012) Nouvelle Flore de la Belgique, du Grand-Duché de Luxembourg, du Nord de la France et des Régions voisines (Ptéridophytes et Spermatophytes). Sixième édition. Jardin botanique national de Belgique, Meise: CXXXIX + 1195 p.

Mabberley D.J. (2008) Mabberley’s plant-book (3th ed.). Cambridge University Press, Cambridge: XVIII + 1021 p.

Nelson E.C. (1997) Moraceae. In: Walters S.M. & al. (eds.), The European Garden Flora, vol. 3. Cambridge University Press, Cambridge: 86-102.

Sytsma K.J., Morawetz J., Pires J.C., Nepokroeff M., Conti E., Zjhra M., Hall J.C. & Chase M.W. (2002) Urticalean rosids: Circumscription, rosid ancestry, and phylogenetics based on rbcL, trnL–F, and ndhF sequences. Am. J. Bot. 89(9): 1531-1546. [available online at:]

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith