Penstemon angustifolius Nutt. ex Pursh 

 Scrophulariaceae 

 Narrowleaf penstemon 

 Description 



1. General description: Perennial herb usually 1.5-4.5 dm 

 (6-18 in) arising from a woody crown, with distinctively firm, 

 glaucous leaves. The flowers have glabrous anthers and a 

 corolla which is glabrous externally, making up an 

 infloresence in a tight compound cluster. The sepals are less 

 than 7 mm (.28 in) long, and the cauline leaves are linear to 

 lanceolate or lanceolate, short to long acuminate or acute 

 (from Great Plains Flora Association 1986) . 



2. Technical description: Slender to stout herbaceous 

 perennial, stems erect to assurgent, (1)1.5-4.5(6.5) dm tall, 

 glabrous or scabrid-puberulent and usually distinctly glacous, 

 1-5(10) stems arising from a woody crown or short-branched 

 woody caudex surmounting a taproot. Leaves entire, glabrous 

 to sparingly oblanceolate, (2.5)4-9 cm long, 0.2-1.8 cm wide, 

 acute to obtuse, subsessile to petiolate, the petioles usually 

 winged; cauline leaves linear to lanceolate or lance-ovate, 3- 

 11 cm long, leaves egualing or commonly much longer than the 

 internodes. Thyrse 4-30 (37) cm long, with (3)5-15 (26) 

 verticillaster, distinctly interrupted to compact, cylindrical 

 and not secund, cymes (2)4- 8 (10) -flowered; bracts lanceolate 

 to lance-ovate or seldom ovate, gradually reduced upward, 

 acute to long-acuminate, bases scarcely clasping to cordate- 

 clasping and overlapping, lower bracts occasionally concealing 

 the pedicels in wide-bracted plants. Calyx glabrous and 

 glaucous to scarcely scabrid-puberlent , lobes lanceolate to 

 lance-ovate, 4-8 mm long, 1-2.5 mm wide, acute or more 

 frequently acuminate, margins scarious, particularly near the 

 base, entire to sub-erose; corolla 14-20(23) mm long, tubular- 

 salverform, moderately ampliate and scarcely ventricose 

 anteriorly, plaited internally and lined on the lower lips 

 projecting to spreading, palate glabrous or sparingly 

 pubescent with whitish densely bearded at the tip with golden- 

 yellow hairs to 1 mm long and more sparingly bearded for 

 slightly more than 1/2 its length; anther sacs (0.9)1.1-1.5 mm 

 long, papillose along the sutures, divergent, dehiscing nearly 

 to the apices and across the connective, not becoming 

 explanate; style glabrous. Capsule 9-14 mm long; seeds 2.5-3.5 

 mm long, angular, brown to dark brown (Great Plains Flora 

 Association 1986) . 



3. Diagnostic characteristics: The most distinguishing 

 characters are the firm linear to narrowly lanceolate or 

 oblanceolate leaves, many of them over 7X as long as wide, 

 with narrow, lanceolate bracts in the inflorescence, usually 

 glaucous appearing, and the plant being completely glabrous. 

 This serves to distinguish the species in the study area even 



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