Taxon Report

Clarkia jolonensis Parnell

Jolon clarkia

Print Report

Taxon Summary

Clarkia jolonensis, commonly known as Jolon clarkia, is a annual herb in the Onagraceae that is found only in California. It occurs within Chaparral, Cismontane woodland, Coastal scrub, and Riparian woodland, growing at elevations from 20 to 660 meters. Clarkia jolonensis is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Clarkia jolonensis Parnell
Common Name:	Jolon clarkia
Family:	Onagraceae
Element Code:	PDONA050L0
USDA Plants Symbol:	CLJO2
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Apr-Jun	Apr-Jun
Elevation:	20-660 (65-2165)
General Habitats:	Chaparral, Cismontane woodland, Coastal scrub, Riparian woodland
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G2
State Rank:	S2
State List:	None
Fed List:	None
Other Status:	SB_SBBG; USFS_S
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	21
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	2
Fair (C)	0
Poor (D)	2
None (X)	6
Unknown (U)	11

Location


California Endemic: True
California Counties and Islands: Name (Code)
Monterey (MNT)
Quads: Name (Quad Code)
Big Sur (3612137), Bryson (3512171), Chews Ridge (3612135), Cosio Knob (3612112), Espinosa Canyon (3612111), Hames Valley (3512088), Jolon (3512182), Monterey (3612158), North Chalone Peak (3612142), Partington Ridge (3612126), Pfeiffer Point (3612127), Seaside (3612157), Soberanes Point (3612148), Soledad (3612143), Sycamore Flat (3612134), Williams Hill (3512181)

Threat List Data from the CNDDB


Threat List Total:	7
EOs with Threat Listed:	Total EOs	% of EOs
	7	33 %
Other	3	14%
Development	2	9%
Non-native plant impacts	2	9%
Dam/Inundation	1	4%
Erosion/runoff	1	4%
Foot traffic/trampling	1	4%
Road/trail construction/maint.	1	4%

Notes



Can be confused with C. lewisii. Threatened by grazing. Possibly threatened by foot traffic and non-native plants. See Madroño 20(6):322 (1970) 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 30 January 2025].