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Native Wildflowers of the North Dakota Grasslands

JPG -- species photo

Blue Beardtongue (Penstemon nitidus)


The gorgeous blue beardtongue would have made a good state flower, as western North Dakota seems to harbor greater numbers of this species than any other state. Elsewhere, there are only scattered records of the plant from southern Manitoba to British Columbia south to South Dakota and Wyoming.

Blue beardtongue is perennial from a thick crown or short-branched woody stem base (caudex) atop a taproot. Individuals are known to have lived ten years. Stems can occur singly, but healthy old individuals can have over a dozen. Most North Dakota specimens are about a foot tall. Leaves and stems are smooth and covered with a waxy bloom. Lower leaves are lance-shaped and three to four inches long; upper ones are broader, but shorter and clasp the stem. Each stem bears on its upper half about 10-20 deep blue flowers about a half inch long. Ripe capsules are tan and contain several dozens of angular brown seeds.

Look for blue beardtongue in early to mid June on rocky or gravelly soils on native prairie slopes. Like many prairie plants in North Dakota, more blue beardtongue seems to be found in heavily or moderately grazed grasslands. But in more arid areas to the Southwest, plants are more numerous where grazing is light.

Blue beardtongue is a member of the figwort family (Scrophulariaceae), which contains about 4,000 species. The family name was derived from the supposed cure of scrophula and figwarts attributed to members of this group by the early European herbalist-physicians. Except for the foxglove, the source of the heart stimulant digitalis, none of the members of this family is of noteworthy economic importance, but many, like the snapdragon, are cultivated for their handsome flowers.

Beardtongues get their name from the single sterile stamen that bears a tuft of hairs. This thread-like male organ protrudes from the flower like a "tongue." There are four fertile stamens as well, hence the generic name Penstemon from the Greek paene, "almost," and stamon, "thread" (filament) or "almost a stamen." There are about 300 species in this genus; most are found in the western United States. The specific name nitidus means "shining" in botanical Latin, possibly because of the almost metallic luster of the flowers.

As a member of the Royal Horticultural Society, ardent Scottish botanist David Douglas (1798-1834), first collected and named blue beardtongue for science. However, it was not until 1846 that the eminent English taxonomist George Bentham had the name published in the tenth volume of the Prodromus. The Prodromus was a fundamental work in the development of plant taxonomy and resulted from a monumental effort by the Swiss-French deCandolle family to create a worldwide flora. Never completed, writing began in 1816 and continued for 102 years! Remarkably, the Prodromus is still the only systematic treatment available for some groups of plants.


Previous Species -- Large Beardtongue (Penstemon grandiflorus)
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