Easily over looked and often under appreciated, Prickly-ash, Zanthoxylum americanum is a native plant next to impossible to find in cultivation. The name lends itself to misunderstanding as well, considering it is not an ash at all. In fact, it is a member of the Rutaceae or the citrus family. It is found along wood edges as 8-10' tall multi-stemmed shrub. It has compound, dark green leaves and the stems have sharp prickles.
This dioecious plant has male and female flowers on separate trees. The small but fragrant female flowers ripen into clusters of rounded, reddish-brown, berry-like fruits. These fruits, which I have been harvesting in an attempt to cultivate, have a wonderfully citrus smell. The seeds of other closely related species are used as an Asian culinary spice. Native Americans chewed the bark or fruits for relief from toothache pain, hence one of the common names: toothache tree.
But, perhaps its most endearing quality are the Giant Swallowtails which hone into these shrubs as their favored Ohio host plant. Once you have seen these gentle Giants, you'll want Prickly-ash in your landscape too!