Species Identification

Interested in the identification of penstemons? Please select a species then click on submit:

AttributeThe current selection is Penstemon_whippleanus
ClassificationPenstemon Penstemon Penstemon Humiles
GeneralWhipple’s Penstemon [syn: P. metcalfei, P. glaucus var stenosepalus, P. arizonicus] Two distinct color forms exist. The dull white or pinkish form exists only in the Great Basin. A dark purple, nearly black form is found in high elevations of CO and other areas. Both forms may be found in the Wasatch and Uinta mts., Utah Plateaus and Laccolithic mts of se UT with no intermediates, suggesting one or few linked genes are responsible. (N. Holmgren, Genus Penstemon, Intermountain Flora). The editor has seen the two forms in the same meadow at Loveland Pass, CO. Blooms: June to August
Anther1.0-1.4 mm long, opening the full length, becoming opposite and eventually flat.
StaminodeWhite, varies from exserted to included in flower with a tuft of yellow hairs at the tip.
LeavesBasal ones 4-9 cm (1 ½-3 ½”) long, & 10-30 mm (¼-1”) wide, lanceolate or ovate, entire or dentate; cauline ones 2.5-6 cm (1-2 ¼”) long, 3-15 mm (<1/2”) wide, narrowly lanceolate to lanceolate or oblanceolate, stemless, cordate-clasping, long-stemmed.
StemsHerbaceous perennial, 2-6 dm (8-24”) tall with well developed basal leaves; stems erect or ascending, clustered on a branched, woody caudex (root base), herbage smooth below, becoming glandular-pubescent (sticky-fuzzy) above.
InflorescenseThyrse of 2-5 congested verticillasters, the cymes 2-4 flowered, secund (one-sided), glandular-pubescent.
Corolla20-27 mm (3/4-1”) long, creamy yellow, white to lavender, maroon, blue, violet or often black-purple, glandular –pubescent, externally, abruptly ventricose-ampliate, bulging roundly, especially lower side, strongly 2-lipped, upper lip short and arched up, the lower one projecting and much exceeding the upper, 2-ridged beneath, palate long, white, hairy. (light forms only found in Great Basin, sw MT, se ID).
Flower Color
Calyx7-10 mm (1/4-3/8”) long, sepals narrowly lanceolate to lanceolate, acuminate at tip, edges often ragged.
HabitatFrom subalpine woodlands and open slopes to timberline and sometimes on alpine tundra 2500-3600 m (8300-11,900’).
RangeAcross intermountain basin: Cassia Co., w and s WY, sw MT, se ID, s. through UT (except Bonneville Flats), CO to n AZ and NM.