Also known as Common Prickly Ash, this plant gets its name from the fact that chewing on the leaves or bark can leave the mouth, teeth, and gums feeling tingly and numb, a symptom that was once used to treat toothaches. This aromatic, perennial shrub often grows in thickets 12 to 25 feet in height. The stems grow thorns at the nodes and small greenish flowers that give way to small red/black fruits. This plant grows in full sun and in rocky, calcareous soils, and attracts various species of butterflies.