Penstemon is the largest plant genus native to North America. Its 280 species (389 taxa) are divided up into six subgenera, 12 sections, and 23 subsections. Most of the species are found in the mountains of the western states, with the center of diversity found in Utah, Colorado, California and Nevada. Most species are pollinated by bees, but there are also adaptations for wasp, butterfly, and hummingbird pollination.
The Penstemon gallery is divided into sections:
Introduction (this page)
Penstemons A-F
Penstemons G-L
Penstemons M-R
Penstemons S-Z
All photos by Andi Wolfe (© – All rights reserved) unless otherwise noted.
Penstemon of the day archive
Some basic information about morphology as it relates to pollinators:
Penstemon palmeri. Penstemons are called the beardtongues for a good reason. Most species have a staminode with bristles. Four anthers are in two pairs at the top of the flower, but the staminode curves down to the floor of the corolla tube. The staminode has a function in pollination.
Penstemon palmeri
Most species of Penstemon are pollinated by insects. However, there are many species that are pollinated by hummingbirds, such as P. eatonii. Notice that the staminode is glabrous (sans bristles). That’s an adaptation for bird pollination.
Penstemon eatonii. Hummingbird-pollinated penstemons are red and have long, narrow corollas.
Penstemon barbatus. Some of the bird-pollinated species have a lower lip that is reflexed.
Penstemon gallery navigation:
Introduction (this page)
Penstemons A-F
Penstemons G-L
Penstemons M-R
Penstemons S-Z
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