Stem. - Sticky, hairy, branching. Leaves. - Usually opposite, rounded, lance-shaped. Flowers. - Deep purplish-pink, solitary or in racemes. Calyx. - Tubular, slightly spurred at the base on the upper side, six-toothed at the apex, usually with a slight projection between each tooth. Corolla. - Small, of six unequal petals. Stamens. - Eleven or twelve, of unequal sizes, in two sets. Pistil. - One, with a two-lobed stigma.

In the dry fields and along the roadsides of late summer this plant is found in blossom. Its rather wrinkled purplish-pink petals and unequal stamens suggest the flowers of the spiked loosestrife, L. Salicaria, to which it is closely related.