Taxon Report

Clarkia imbricata Lewis & Lewis

Vine Hill clarkia

Print Report

Taxon Summary

Clarkia imbricata, commonly known as Vine Hill clarkia, is a annual herb in the Onagraceae that is found only in California. It occurs within Chaparral, and Valley and foothill grassland, growing at elevations from 50 to 75 meters. Clarkia imbricata is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Clarkia imbricata Lewis & Lewis
Common Name:	Vine Hill clarkia
Family:	Onagraceae
Element Code:	PDONA050K0
USDA Plants Symbol:	CLIM
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Jun-Aug	Jun-Aug
Elevation:	50-75 (165-245)
General Habitats:	Chaparral, Valley and foothill grassland
Microhabitat:	Acidic, Loam, Sandy
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.1
Global Rank:	G1
State Rank:	S1
State List:	CE
Fed List:	FE
Other Status:	SB_CalBG/RSABG; SB_UCBG
CRPR Changes:

Occurrence Data from the CNDDB


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

Location


California Endemic: True
California Counties and Islands: Name (Code)
Sonoma (SON)
Quads: Name (Quad Code)
Sebastopol (3812247)

Threat List Data from the CNDDB


Threat List Total:	8
EOs with Threat Listed:	Total EOs	% of EOs
	2	100 %
Non-native plant impacts	2	100%
Other	2	100%
Agriculture	2	100%
Development	2	100%
Wood cutting or brush clearing	2	100%
Hybridization	1	50%
Over-collecting/poaching	1	50%
Road/trail construction/maint.	1	50%

Notes



Known from only two extant occurrences, one of which is introduced; a third, natural occurrence has been extirpated. Threatened by development and road maintenance. See Madroño 12(2):38 (1953) 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 31 January 2025].