Taxon Report

Arenaria lanuginosa (Michx.) Rohrb. var. saxosa (A. Gray) Zarucchi et al.

rock sandwort

Print Report

Taxon Summary

Arenaria lanuginosa var. saxosa, commonly known as rock sandwort, is a perennial herb in the Caryophyllaceae that is found in California and elsewhere. It occurs within Subalpine coniferous forest, and Upper montane coniferous forest, growing at elevations from 1455 to 2600 meters. Arenaria lanuginosa var. saxosa is ranked 2B.3, Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere; Not very threatened in California.

Classification


Scientific Name:	Arenaria lanuginosa (Michx.) Rohrb. var. saxosa (A. Gray) Zarucchi et al.
Common Name:	rock sandwort
Family:	Caryophyllaceae
Element Code:	PDCAR040E4
USDA Plants Symbol:
Synonyms/Other Names:	Arenaria lanuginosa ssp. saxosa

Ecology and Life History


Lifeform:	perennial herb
Blooming Period: Jul-Aug	Jul-Aug
Elevation:	1455-2600 (4775-8530)
General Habitats:	Subalpine coniferous forest, Upper montane coniferous forest
Microhabitat:	Mesic, Sandy
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	2B.3
Global Rank:	G5T5
State Rank:	S2
State List:	None
Fed List:	None
Other Status:	SB_CalBG/RSABG; USFS_S
CRPR Changes:	changed from 2.3 to 2B.3 on 2013-06-12

Occurrence Data from the CNDDB


Total Occurrences:	15
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	6
Poor (D)	0
None (X)	0
Unknown (U)	9

Location


California Endemic: False
California Counties and Islands: Name (Code)
San Bernardino (SBD)
Quads: Name (Quad Code)
Big Bear Lake (3411628), Forest Falls (3411618), Moonridge (3411627), San Gorgonio Mtn. (3411617)

Threat List Data from the CNDDB


Threat List Total:	3
EOs with Threat Listed:	Total EOs	% of EOs
	6	40 %
Foot traffic/trampling	6	40%
Over-collecting/poaching	1	6%
Recreational use (non-ORV)	1	6%

Notes



Possibly threatened by foot traffic. See Smithsonian Contributions to Knowledge 5(6):18 (1853) for original description, and American Midland Naturalist 46(2):498 (1951) 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 14 May 2025].