Taxon Report

Cleomella palmeri (A. Gray) J.C. Hall & Roalson

Palmer's jackass-clover

Print Report

Taxon Summary

Cleomella palmeri, commonly known as Palmer's jackass-clover, is a perennial deciduous shrub in the Cleomaceae that is found in California and elsewhere. It occurs within Chenopod scrub, Desert dunes, Sonoran desert scrub, and Sonoran thorn woodland, growing at elevations from 0 to 300 meters. Cleomella palmeri is ranked 2B.1, Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Cleomella palmeri (A. Gray) J.C. Hall & Roalson
Common Name:	Palmer's jackass-clover
Family:	Cleomaceae
Element Code:	PDCPP09015
USDA Plants Symbol:	WIREP
Synonyms/Other Names:	Wislizenia refracta Engelm. ssp. palmeri (A. Gray) S. Keller

Ecology and Life History


Lifeform:	perennial deciduous shrub
Blooming Period: Jan-Dec	Jan-Dec
Elevation:	0-300 (0-985)
General Habitats:	Chenopod scrub, Desert dunes, Sonoran desert scrub, Sonoran thorn woodland
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	2B.1
Global Rank:	G5T3T5
State Rank:	S1
State List:	None
Fed List:	None
Other Status:
CRPR Changes:	changed from 2B.2 to 2B.1 on 2024-02-27 changed from 2.2 to 2B.2 on 2013-06-12 added to 2.2 on 2010-06-10

Occurrence Data from the CNDDB


Total Occurrences:	4
Element Occurrence Ranks:
Excellent (A)	1
Good (B)	0
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	3

Location


California Endemic: False
California Counties and Islands: Name (Code)
Riverside (RIV), San Diego (SDG)
Quads: Name (Quad Code)
Borrego Palm Canyon (3311634), Borrego Sink (3311623), Clark Lake (3311633), Corn Spring (3311563), East of Victory Pass (3311573), Sidewinder Well (3311562), Tubb Canyon (3311624)

Threat List Data from the CNDDB


Threat List Total:	4
EOs with Threat Listed:	Total EOs	% of EOs
	2	50 %
Development	2	50%
ORV activity	2	50%
Agriculture	1	25%
Groundwater pumping	1	25%

Notes




Threats:
Threatened by solar energy development and agriculture.
Taxonomy:

Selected References

CRPR List Addition on 2010-06-10

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 24 October 2025].