Zanthoxylum
GENERAL:
These small trees are members of the same plant family as citrus.The most common species is Z. clava-herculis, called Hercules’ club.It can grow to 15 m. (45 ft.).Three other species are on the Florida Endangered Species List:Z. americanum (called Toothache Tree is found only in Gadsden & Jackson Counties), Z. coriaceum (called Biscayne Prickly Ash is found in coastal hammocks from Brevard Co. south) and Z. flavum (called Yellow Heart is extremely rare in the southern Keys.)
The bark and seeds have long been used in Indian and folk medicine as a treatment for rheumatism, and the sap has a numbing quality that gives it the common name, Toothache Tree.
An important tree to wildlife, the oily black fruits provide food to fall-migrating songbirds such as the Great Crested Flycatcher and Eastern Kingbirds.
FLOWERS / FRUIT:
The
greenish yellow flowers appear in terminal clusters.They
are followed by seed pods which hold flat, shiny black seeds ripening
in
late summer.Z. americanum has
flowers with red tipped green petals born in axillary clusters.
PRICKLY ASH or HERCULES CLUB(Zanthoxylum clava-herculis)
LEAVES / STEMS:
The alternate, pinnately compound leaves have 7 to 20 leaflets arranged along a rachis (midrib) that has sharp thorns.The glabrous (smooth) dark green leaves are aromatic, smelling similar to citrus.Z. americanum are pubescent on lower surface.Z. coriaceum has even pinnate leaves.
The sharp thorns along the leaves, branches and young trunks are identifying characteristics.Older trunks lose the thorns, but have bumps on the bark. Z. americana is distinguished by thorns mostly in pairs at the nodes rather than along the stem.
DISTRIBUTION:
Z.
clava herculis
is found in wet woods and hammocks nearly throughout Florida, following
the coastal plain to Texas and Arkansas and north to Virginia.See
first paragraph for other species.