Spring is over, and in its departure the blossoming of the hairy penstemon appears on the rocky hills and dry slopes of Illinois. The penstemon comes as a final gesture of May. an introduction to June and high summer. Yet penstemon still has something of the quality of spring flowers, but has that sturdiness also which is common to summer blossoms.
Penstemon hirsutus (L.) Willd.
May - June Dry woods, hills.
Hairy penstemon on a dry, sunny Illinois hill has a straight tall stem decorated with pairs of opposite, hairy, stemless, tapering leaves. The flower head is plumy and large, the small stems downy and often a. spiderweb is strung among them. The flowers are tubular, white or lavender-white, with purple bee-lines in the throat. All of the flower trumpets face outward in a loose, globular cluster. The tubular flower is five parted, with a three-lobed lip much as in the mints. The throat is densely bearded, hence the name of beard tongue which is often given to the penstemons. They are constructed in such a manner that only specialized insects may push through for the nectar at the end of the tube. In addition to the above there are at least six other species of penstemons in Illinois. Two deserve special mention. The pale beard tongue (Penstemon pallidas) with downy leaves, tall nearly smooth stems, and nearly white flowers that are short-tubular, is found in dry wooded slopes. The foxglove penstemon (Penstemon digitalis) perhaps is most frequently found throughout the state. It grows in dry and moist soils and often forms large colonies of plants which grow 3 to 5 feet tall, with smooth leaves. The flowers are white or purplish, the corolla a little more than an inch long and gradually enlarged upward.