This perennial plant is 3-12' tall. Plants in dense colonies are only 3-5' tall, but 'lone wolf' plants can achieve considerable height. The stout central stem is glabrous, glaucous, terete (circular in cross-section), and often reddish or reddish-purple in color. There is very little branching, except for some flowering stems that occur along the upper half of the plant. The leaves are up to 8" long and 2½" across, lanceolate-oblong, and either smooth (entire) or slightly to strongly serrate along their margins. The upper leaf surface is medium to dark green with a sandpapery texture that derives from the presence of minute stiff hairs. The lower leaf surface is pale green and softly hairy. The leaves are often slightly recurved, and they have a tendency to fold upward along their central veins, particularly during hot dry weather. The leaves are opposite below, but they become either alternate or opposite along the upper half of the plant. The leaves taper gradually into slender petioles that are about ½" in length.