The Smooth Beardtongue (Pentstemon pentstemon (Linnaeus) Britton (figure XXVIII), P. laevigatus Solander) is smooth except the somewhat glandular inflorescence; the tube of the corolla gradually enlarged above, its throat wide open and scarcely or not at all bearded. Common in woods, thickets and fields; native from Pennsylvania southward.

Figure XXVIII   Smooth Beardtongue (Pentstemon pentstemon (Linnaeus) Britton)

Figure XXVIII - Smooth Beardtongue (Pentstemon pentstemon (Linnaeus) Britton)

The Foxglove Beardtongue (Pentstemon digitalis (Sweet) Nuttall), also probably an escape in this part of its range, is similar to the Smooth Beardtongue, but the leaves are somewhat broader and more clasping at the base; the corolla is white and 1 to 11/2 inches long, abruptly expanded upward and the throat wide open.