Potentilla sierrae-blancae (Sierra Blanca Cinquefoil)

Potentilla sierrae-blancae (Sierra Blanca Cinquefoil)

Photograph by Tyler Johnson (2010)
Family
ROSACEAE
Scientific Name with Author
Potentilla sierrae-blancae Wooton & Rydberg
Synonyms
NONE
Common Name
Sierra Blanca Cinquefoil
Rare Plant Conservation Scorecard Summary
Overall Conservation Status Documented Threats Actions Needed
MODERATELY CONSERVED

Fire and fire supression. Recreational impacts (trampling).

Trend monitoring. Document threat impacts. Seed banking.


County Map
Counties
Description
Perennial herb to 8 cm tall; stems and rootstocks numerous, short, and almost matted, appearing caespitose; leaves digitately 5-foliate; leaflets divided terminally into three lobes; leaflet bases narrowly cuneate; midvein of leaflets raised on lower surface; lateral veins seen as faint lines on lower surface and impressed to some degree on upper surface; leaflets with ciliate margins; cilia on leaf margins up to 2.0 mm long, remote; petioles to 35 mm long, often bearing scattered cilia; largest leaflets to 20 mm long; flowering stems occasionally branched from lower of usually two nodes; flowers solitary at end of peduncle 10-35 mm long; peduncles and lower parts of flowering stem usually villous; petals 5, yellow, about 7 mm long; calyx villous; outer series of 5 bractlets narrowly oblong and obtuse, sparsely long-villous, about 3 mm long, 1 mm wide, with thin reddish margins; sepals 4-4.5 mm long, sparsely long-villous, broad at base, acute at tip; margins scarious in basal 1/3 of each sepal, thin and reddish in distal 2/3; styles terminal. Flowers in June and July.
Similar Species
This species is easily separated from most in the genus by its short habit and narrow, 3-toothed leaflets. The allopatric Potentilla bicrinata also has 3-toothed leaflets, but they are wider and tomentose on the lower surface.
Distribution
New Mexico, southern Lincoln and northern Otero counties, White Mountains.
Habitat
Open windswept crests of ridges and mountain tops on igneous rock substrate with thin soil at 3,350-3,660 m (11,000-12,000 ft); occasionally found on igneous cliffs and outcrops in canyons as low as 2,440 m (8,000 ft).
Remarks
The species occupies a niche where little else can grow. It forms a ground cover on almost barren ridges that are subject to high winds and extremes of temperature. The density of plants can be up to 15/m.
Conservation Considerations
This plant is not significantly threatened by current land uses within its habitat.
Important Literature

*New Mexico Native Plants Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. University of New Mexico Press, Albuquerque.

*Wooton, E.O. and P.A. Rydberg. 1898. [Description of Potentilla sierrae-blancae]. Memoirs from the Department of Botany of Columbia University 2:57.

Information Compiled By
Richard D. Worthington 1999

For distribution maps and more information, visit Natural Heritage New Mexico