Penstemon angustifolius var. caudatus

Plant Information
Species: 
angustifolius
Species Authority: 
Nutt. ex Pursh
Variety: 
caudatus
Variety Authority: 
(A. Heller) Rydb.
Subgenus: 
Penstemon
Section: 
Coerulei
Habit:
 
herbaceous perennial
Habit Woodiness:
 
herb
Lifespan: 
short-lived
Plant Height - Min: 
2.00dm
Plant Height - Max: 
4.00dm
Habitat Description: 
In Colorado, on the sand hills and other sandy areas of the plains.
Distribution Range: 
Eastern Kansas to eastern Colorado and southward to northern New Mexico and western Oklahoma. In Colorado, from Weld County eastward and southward. One specimen also from Montezuma County of the western slope.
Soil Type: 
Sandy soils.
Elevation - Min: 
900.00m
Elevation - Max: 
2300.00m
Other Notes: 

P. angustifolius appears not to occur in the southern range of the subspecies, while the latter does not occur in the northern part of the range of the species. The broader, and often caudate, bracts upon which P. caudatus was based, show such complete intergradation with the narrower ones of the species, that the assignment of many specimens in the overlapping ranges is wholly arbitrary. In the subspecies, the plants are generally more robust. In addition, the color of the corolla in the subspecies is often lighter than in the suggesting a delicate balance of the hydrogen ion concentration in the cell sap for expression of the blue or pink anthocyan pigments.

First Bloom: 
Late April
Last Bloom: 
June
Chromosome Number: 

2n = 16

References: 

Harrington, HD. 1964. Manual of the plants of Colorado. Denver, Colorado: Sage Books.