American germander is a colony-forming perennial with a 4-sided, hairy stem that is rarely branched. Flowers are lavender or pink, in terminal and lateral racemes, densely spaced. The corolla has an unusual configuration; it seems to have no upper lip, since those 2 lobes are pointed upward like horns, while the lower lip is much larger and more complicated, with 2 rounded side lobes and a large, cupped, bottom lobe; 4 stamens protrude noticeably, with reddish-brown anthers. Blooms June–September. Leaves are opposite, lanceolate, sharply pointed; on petioles; with sharp or rounded teeth. Crushed foliage has a slightly foul odor.
Similar species: Two varieties of this species have been recorded for Missouri, and they are difficult to tell apart. American germander has several characteristics in common with its mint-family relatives, such as the square stems, opposite leaves, and two-lipped flowers. But this is the only mint in our state with the unique corolla lobe configuration.
Height: to about 3 feet.
Statewide.
Habitat and Conservation
Occurs in fields, prairies, low woods, streamsides, roadsides, railroads, and other disturbed sites, usually in moist soil.
Human Connections
Germander had many medicinal uses — to induce menstruation and urination, to cause sweating, and to treat lung and throat ailments, intestinal parasites, and external wounds.
Native plant gardeners use American germander in herb gardens and naturalized around ponds and streams. The flowers are probably less showy than the overall effect of the foliage, though the flowers provide nectar to hummingbirds.
The English name "germander" is ancient and apparently has always referred to plants in this genus. It seems to have derived ultimately from an old Greek word, chamaidrys (chaimai = "on the ground"; drys = "tree"), meaning "humble tree." Apparently the look of the leaves or growth habit of Old World members of this genus looked like small oaks or other trees. Indeed, the wall germander, a species native to the Mediterranean region, is Teucrium chamaedrys.
The genus name, Teucrium, also has links to the ancient Mediterranean: Linnaeus, who first described the genus in the 1700s, apparently used a name that ancient Greek writers had bestowed on it, after a legendary King Teucer, son of a river deity and a nymph, said by many to be the first king of Troy. The idea is that King Teucer had used plants in this genus medicinally.
Ecosystem Connections
As with the elaborate floral structures of orchids, the flowers are elegantly adapted for insect pollination. A variety of insects are guided to the nectar and pollen by the dark purple spots on the large lower lip. The broad lower lip is a fine landing pad for flying insects. Principal insect visitors are long-tongued bees such as bumble bees, honeybees, leafcutter bees, digger bees, and miner bees. A variety of other small bees, flies, butterflies, skippers, and hummingbird moths take nectar.
Hummingbirds visit the flowers, too.
This and other native mints are eaten by a variety of insects, including the caterpillars of certain noctuid moths, but certainly also many other kinds of insects as well. These insects are eaten by a wide range of insectivores, such as other insects and spiders, bats, lizards, frogs, and birds.
Mammals such as deer and rabbits don't tend to browse the plant, apparently because it is bitter.
Plants like these, which colonize disturbed soils and the land along streams, play an important role in preventing erosion and filtering pollutants and silt from riverways.