Penstemon (10)
Penstemon is a very large genus that is easy to recognize, but not so easy to identify individual species. The flowers are tubular with two lips; the upper lip is two-lobed and the lower is three-lobed. The leaves are opposite without stalks. The flowers can be blue, purple, lavender, pink or red. See Beardtongue, Scarlet Penstemon, Mat Penstemon, Palmer's Penstemon and other Penstemon in Blue Long Clusters. There is a great deal of passion about Penstemon amongst horticulturists on the Internet but the best key I found was from 1915 by Francis Whittier Pennell, Scrophulariaceae of the Central Rocky Mountains. It is charming to read his introduction of traveling along on the Rio Grande Railroad to make his collections. So much has changed and yet so little in 100 years. The American Penstemon Society also has a lot of information.
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Rocky Mountain Penstemon Family:Plantain (Plantaginaceae) Grows to 3 feet tall in showy masses. Flowers range from pale lavender to purple, are hairless and grow on one side of the stem. It is the most common and tallest Penstemon in the Gunnison Valley. Rocky Mountain Penstemon, below at left, has hairs on the anthers and few or none on its tongue, which distinguishes it from the similar looking Grand Mesa Penstemon, below at right, whose anthers have few hairs and its tongue has long orange hairs at the tip. Flora of North America reference. |
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Grand Mesa Penstemon Family:
Plantain (Plantaginaceae) Grows to 18" with non-hairy leaves. Flowers are an intense electric blue or purple-tinged blue and are minutely fuzzy on the outside. They are less than 1" long, shorter than the Rocky Mountain Penstemon. Flowers grow in whorls mostly on one side of the stem. It is quite common in Mesa, Delta and Gunnison counties but not found in the wild elsewhere and is listed as a Colorado Rare Plant. Flora of North America reference. |
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Upland Penstemon Family: Plantain (Plantaginaceae) Grows 4" to 20" high with smooth, hairless, narrow, lance-shaped leaves. The deep blue flowers are 1" long and grow all around the stem compared to Rocky Mountain Penstemon. Flora of North America reference. |
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Narrow-Leaved Penstemon Family:
Plantain (Plantaginaceae) Grows to 20" with stout smooth stems and fleshy, narrow leaves with a prominent mid-rib. Stems and leaves are light green and hairless. The flowers are lavender to bright blue and grow all around the stem. The sterile stamen has orange hairs on its tip. Flora of North America reference. |
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Sawsepal Penstemon Family:
Plantain (Plantaginaceae) Can grow to 24" with large leathery bright green leaves opposite on the stem. The blue flowers have pink throats and grow on one side of the stem. The sepals are rounded with a short, sharp tip. Penstemon glaber has several varieties. They all have bright green, hairless leaves clasping the stem, some are thicker and leathery, shape varies from lance-shaped to almost triangular, some smooth-edged others wavy. Below are two varieties. Flora of North America reference. |
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Alpine Sawsepal Penstemon Family:
Plantain (Plantaginaceae) Grows 4" to 18" east of the Continental Divide but not in the alpine zone, despite its name. Leaves are smooth, lance-shaped and medium green. Showy flowers, about an 1" long, grow on one side of the thick stems. The sepals are oval-shaped and pointed. The sterile stamen is slender and not lobed. Flora of North America reference. |
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Brandegee's Penstemon Family:
Plantain (Plantaginaceae) Grows to 2½ feet, very robust and stockier than P. glaber and P. alpinus. Leaves are broadly lance-shaped and clasp the stem. Flowers are showy, intense blue-purple crowded on one side of the stems and 1½" long. Sepals are oval with a long tip. The sterile stamen is stout with two lobes and sticks out of the throat. Nobody mentions the crinkly-edged leaves. Flora of North America reference. |
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Hall's Penstemon Family:
Plantain (Plantaginaceae) Grows to 8" with bluish-purple flowers on one side of the stem. Leaves are narrow and entire. It only grows in central and southwest Colorado. Flora of North America reference. |
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Front Range Penstemon Family:
Plantain (Plantaginaceae) Grows to 12" high from mats of bright green, hairless leaves. Flowers are bright blue to blue violet with a pale throat with maroon stripes and are ½" long. The outside of the flowers has hairs and the beardtongue has orange hairs. Flowers grow all around the stem. It only grows east of the Divide.
Flora of North America reference. |
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Oneside Penstemon Family:Plantain (Plantaginaceae) Grows to 2 feet with flowers on one side of the stem. Leaves are long narrow and folded inwards. Flowers are broad with a white throat and strong purple lines, nectar guides. The stamens are white, curved and hairless. The sterile stamen is white, hairless, broader at the tip and extends a little from the throat. This differentiates it from some of the similarly patterned Beardtongues. Flora of North America reference. |
