Range: Maine and Ontario to South Dakota and Colorado, southward to Georgia and Louisiana. Habitat: Swamps, wet meadows, and along streams and ditches.
Like all its family, the juices of this plant are acrid and poisonous. Stem one to three feet tall, rather stout, slightly angled, usually without branches. Leaves large, alternate, thin, dark green, oblong, pointed at both ends, somewhat hairy, irregularly and rather finely toothed, sessile except the lowermost. Flowers in narrow, crowded, leafy, bracted racemes sometimes six inches or more in length, deep blue or occasionally white; corolla nearly an inch long, the tube cleft to the base on the upper side, the two lobes of its upper lip acute but the three lower ones longer and somewhat obtuse; stamens five, united into a tube around the style, with three of the anthers larger than the other two; calyx hairy, with narrow, long-pointed lobes, the sinuses with large, deflexed auricles. The many-seeded, two-celled capsules float easily on water.
Hand-pulling or grubbing from pastures and meadows. Drainage will usually expel the plant from the soil, for it demands moisture.