Hercules club, Toothache tree

Zanthoxylum clava-herculis L.

Rutaceae (Citrus family)


Hercules club is a small to medium-sized tree or shrub in the Citrus family. It is a native, cool-season perennial. The bark of the trunk is light gray and thinly covered with conspicuous, corky, cone-like tubercles (wartlike outgrowths). The twigs are brown to gray and have simple spines.

Hercules club leaves are located alternately along the stems and are pinnately (arranged on a common axis) compound, with spines on the supporting leaf stem. There are usually five to 19 leaflets. The leaves are lustrous, have serrated edges and may be somewhat hairy underneath.

The flowers are greenish white and appear in April and May. The mature fruit is a shiny black seedpod with one seed; the seeds occur in clusters.

Hercules club provides an excellent source of seeds and fruit for birds but has low value for grazing.


This tree commonly grows along fence rows and hedge rows on sandy and clay soils.