Zanthoxylum clava-herculis, commonly known as the Hercules' club, toothache tree, or southern prickly ash, is a spiny deciduous tree or large shrub native to the coastal plains of the southeastern United States.

Belonging to the Rutaceae (citrus) family, this unique perennial typically grows between 10 to 30 feet tall, though it can occasionally reach up to 50 feet in shaded environments. It is most famous for its unique corky, cone-like bark projections and its ability to naturally numb the mouth.

Native Americans and early pioneers chewed the bark, leaves, and twigs to temporarily treat mouth pain. The plant contains an active component, hydroxy-alpha sanshool, which creates a strong tingling and numbing sensation on the tongue

This tree does best in full sun to partial shade and is highly tolerant of sandy, calcium-rich coastal soils, clay, loam and poor dry soils.

It can spread via root suckers to form thickets.

Host plant for the Giant Swallowtail butterfly.