Taxon Report

Castilleja campestris (Benth.) T.I. Chuang & Heckard var. succulenta (Hoover) J.M. Egger

succulent owl's-clover

Print Report

Taxon Summary

Castilleja campestris var. succulenta, commonly known as succulent owl's-clover, is a annual herb (hemiparasitic) in the Orobanchaceae that is found only in California. It occurs within Vernal pools, growing at elevations from 50 to 750 meters. Castilleja campestris var. succulenta is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Castilleja campestris (Benth.) T.I. Chuang & Heckard var. succulenta (Hoover) J.M. Egger
Common Name:	succulent owl's-clover
Family:	Orobanchaceae
Element Code:	PDSCR0D3Z1
USDA Plants Symbol:
Synonyms/Other Names:	Orthocarpus succulentus Orthocarpus campestris Benth. var. succulentus Hoov. Castilleja campestris ssp. succulenta

Ecology and Life History


Lifeform:	annual herb (hemiparasitic)
Blooming Period: (Mar)Apr-May	(Mar)Apr-May
Elevation:	50-750 (165-2460)
General Habitats:	Vernal pools
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G4?T2T3
State Rank:	S2S3
State List:	CE
Fed List:	FT
Other Status:
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	99
Element Occurrence Ranks:
Excellent (A)	15
Good (B)	21
Fair (C)	2
Poor (D)	3
None (X)	2
Unknown (U)	56

Location


California Endemic: True
California Counties and Islands: Name (Code)
Fresno (FRE), Madera (MAD), Mariposa (MPA), Merced (MER), San Joaquin (SJQ), Stanislaus (STA)
Quads: Name (Quad Code)
Berenda (3712012), Cooperstown (3712065), Cressey (3712046), Daulton (3711918), Fresno North (3611977)*, Friant (3611986), Gregg (3611988), Haystack Mtn. (3712043), Humphreys Station (3611984), La Grange (3712064), Lanes Bridge (3611987), Le Grand (3712022), Lockeford (3812122), Merced (3712034), Merced Falls (3712053), Millerton Lake East (3711915), Millerton Lake West (3711916), Owens Reservoir (3712032), Planada (3712033), Raymond (3711928), Round Mountain (3611975), Snelling (3712054), Winton (3712045), Yosemite Lake (3712044)

Threat List Data from the CNDDB


Threat List Total:	11
EOs with Threat Listed:	Total EOs	% of EOs
	34	34 %
Grazing	28	28%
Development	8	8%
Foot traffic/trampling	5	5%
Agriculture	4	4%
Dam/Inundation	3	3%
Other	2	2%
Road/trail construction/maint.	2	2%
Disking	1	1%
Landfill	1	1%
Non-native plant impacts	1	1%
ORV activity	1	1%

Notes



Threatened by urbanization, agriculture, flood control, grazing, and trampling. See C. campestris ssp. succulenta in TJM 2. See Leaflets of Western Botany 1(19):228-229 (1936) for original description, and Systematic Botany 16(4):644-666 (1991) and Phytologia 90(1):63-81 (2008) for revised nomenclature.
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 June 2025].