Taxon Report

Potentilla basaltica Tiehm & B. Ertter

Black Rock potentilla

Print Report

Taxon Summary

Potentilla basaltica, commonly known as Black Rock potentilla, is a perennial herb in the Rosaceae that is found in California and elsewhere. It occurs within Meadows and seeps (alkaline, sandy, and volcanic), growing at elevations from 1360 to 1555 meters. Potentilla basaltica is ranked 1B.3, Plants Rare, Threatened or Endangered in California and Elsewhere; Not very threatened in California.

Classification


Scientific Name:	Potentilla basaltica Tiehm & B. Ertter
Common Name:	Black Rock potentilla
Family:	Rosaceae
Element Code:	PDROS1B270
USDA Plants Symbol:	POBA6
Synonyms/Other Names:

Ecology and Life History


Lifeform:	perennial herb
Blooming Period: May-Jun(Jul)	May-Jun(Jul)
Elevation:	1360-1555 (4460-5100)
General Habitats:	Meadows and seeps
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.3
Global Rank:	G1
State Rank:	S1
State List:	None
Fed List:	None
Other Status:	BLM_S; SB_UCSC; USFS_S
CRPR Changes:	changed from 1B.2 to 1B.3 on 2012-02-24 changed from 1B.3 to 1B.2 on 2012-02-24

Occurrence Data from the CNDDB


Total Occurrences:	2
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	1
Poor (D)	1
None (X)	0
Unknown (U)	0

Location


California Endemic: False
California Counties and Islands: Name (Code)
Lassen (LAS)
Quads: Name (Quad Code)
Ash Valley (4112016)

Threat List Data from the CNDDB


Threat List Total:	4
EOs with Threat Listed:	Total EOs	% of EOs
	2	100 %
Foot traffic/trampling	1	50%
Grazing	1	50%
Other	1	50%
Road/trail construction/maint.	1	50%

Notes



Known in CA from only two occurrences in Ash Valley, and in NV from one occurrence, where threatened. Threatened by trampling and vehicles. Possibly threatened by grazing and road maintenance. Not in The Jepson Manual. See Brittonia 36(3):228-231 (1984) for original description.
Threats:

Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 5 February 2025].