Taxon Report

Chorizanthe pungens Benth. var. hartwegiana Rev. & Hardham

Ben Lomond spineflower

Print Report

Taxon Summary

Chorizanthe pungens var. hartwegiana, commonly known as Ben Lomond spineflower, is a annual herb in the Polygonaceae that is found only in California. It occurs within Lower montane coniferous forest, growing at elevations from 90 to 610 meters. Chorizanthe pungens var. hartwegiana is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Chorizanthe pungens Benth. var. hartwegiana Rev. & Hardham
Common Name:	Ben Lomond spineflower
Family:	Polygonaceae
Element Code:	PDPGN040M1
USDA Plants Symbol:	CHPUH2
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Apr-Jul	Apr-Jul
Elevation:	90-610 (295-2000)
General Habitats:	Lower montane coniferous forest
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.1
Global Rank:	G2T1
State Rank:	S1
State List:	None
Fed List:	FE
Other Status:	SB_UCSC
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	18
Element Occurrence Ranks:
Excellent (A)	1
Good (B)	6
Fair (C)	4
Poor (D)	0
None (X)	1
Unknown (U)	6

Location


California Endemic: True
California Counties and Islands: Name (Code)
Santa Cruz (SCR)
Quads: Name (Quad Code)
Big Basin (3712222), Castle Rock Ridge (3712221), Davenport (3712212), Felton (3712211), Laurel (3712118)

Threat List Data from the CNDDB


Threat List Total:	9
EOs with Threat Listed:	Total EOs	% of EOs
	10	56 %
Development	7	38%
Mining	3	16%
Recreational use (non-ORV)	3	16%
Road/trail construction/maint.	2	11%
Foot traffic/trampling	2	11%
Grazing	1	5%
Logging	1	5%
Erosion/runoff	1	5%
Non-native plant impacts	1	5%

Notes



Known only from sandhill parklands in the Santa Cruz Mtns. Threatened by sand mining, development, and non-native plants. See C. pungens in The Jepson Manual. See Annals of the Missouri Botanical Garden 21:37 (1934) for original description, and Phytologia 66(2):123-126 (1989) for taxonomic treatment, Fremontia 24(4):8-11 (1996) for taxonomic discussion, and Madroño 45(2):119-127 (1998) for ecological information.
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 3 November 2025].