Clematis hirsutissima var. arizonica
|Joyce Maschinski, Ph.D.|
The following Participating Institutions are custodians for this species in the CPC National Collection:
The Arboretum at Flagstaff
The conservation of Clematis hirsutissima var. arizonica is fully sponsored.
Joyce Maschinski, Ph.D. contributed to this Plant Profile.
This taxon's standing as a true variety has been called into question, and a morphological study showed that there was no clear difference between this variety (var. arizonica) and the more common variety (var. hirsutissima). (Pringle 1997) However, the U.S. Forest Service lists it as a sensitive species.
Arizona leatherflower is an herbaceous perennial understory species with purple nodding bell-shaped flowers. It is found on limestone outcroppings in ponderosa pine forest. Plants are 20-70 cm high with erect, weak, or trailing stems emerging from a somewhat woody base. Leaves are pinnately compound with 7-13 leaflets. The showy purple flowers are displayed individually at the end of each stem and become heads of golden feathery seeds in late summer.
These plants may be a great indicator of forest health. Their greatest reproduction occurs in intermediate shade with little forest litter. Extremely heavy shade reduces growth and reproduction, but full sun can dry seeds and plants. In the ponderosa pine forest, this species faces threats including timber harvest, controlled thinning and burning, cattle and elk grazing, and development. (Maschinski & Phillips 1993)
Distribution & Occurrence
- New Mexico
In Arizona, the taxa most commonly grows on soils derived from Kaibab limestone in small colonies in ponderosa pine forests sometimes covering only fractions of an acre. Requires only moderate shade.
Northern reaches of the species habitat is mixed conifer forest and much more mesic than the Arizona populations experience.
Similar Species: the typical variety has narrower leaflets (1-2 mm), smaller flowers, and a 90 degree angle of mature petioles to the stem.
Notes: Erickson rec
|In Arizona there are approximately 1500 individuals. Since the taxa has been lumped with the widespread species the distribution and population numbers have expanded greatly.|
Conservation, Ecology & Research
grazing by cattle and elk
Pringle (1997) completed a floristic review of the genus Clematis in North America, and found no clear differences between C. hirsutissima var. arizonica and C. hirsutissima var. hirsutissima. In response to this, the U.S. Fish and Wildlife Service removed the species from candidate status, as Clematis hirsutissima var. hirsutissima is a widespread taxon. (USFWS 1998)
Pringle, J.S. 1997. Clematis. Flora of North America. Oxford University Press. New York. p 160-176.