Taxon Report

Sidalcea malviflora (DC.) Benth. ssp. purpurea Hitchc.

purple-stemmed checkerbloom

Print Report

Taxon Summary

Sidalcea malviflora ssp. purpurea, commonly known as purple-stemmed checkerbloom, is a perennial rhizomatous herb in the Malvaceae that is found only in California. It occurs within Broadleafed upland forest, and Coastal prairie, growing at elevations from 15 to 85 meters. Sidalcea malviflora ssp. purpurea is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Sidalcea malviflora (DC.) Benth. ssp. purpurea Hitchc.
Common Name:	purple-stemmed checkerbloom
Family:	Malvaceae
Element Code:	PDMAL110FL
USDA Plants Symbol:	SIMAP2
Synonyms/Other Names:

Ecology and Life History


Lifeform:	perennial rhizomatous herb
Blooming Period: May-Jun	May-Jun
Elevation:	15-85 (50-280)
General Habitats:	Broadleafed upland forest, Coastal prairie
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G4G5T1
State Rank:	S1
State List:	None
Fed List:	None
Other Status:	BLM_S
CRPR Changes:

Occurrence Data from the CNDDB


Total Occurrences:	19
Element Occurrence Ranks:
Excellent (A)	1
Good (B)	2
Fair (C)	3
Poor (D)	0
None (X)	0
Unknown (U)	13

Location


California Endemic: True
California Counties and Islands: Name (Code)
Marin (MRN)?, Mendocino (MEN), Sonoma (SON)
Quads: Name (Quad Code)
Bodega Head (3812331), Cazadero (3812351), Drakes Bay (3812218)?, Duncans Mills (3812341), Fort Bragg (3912347), Fort Ross (3812352), Gualala (3812375), Inglenook (3912357), Mallo Pass Creek (3912316), Plantation (3812353), Point Arena (3812386), Saunders Reef (3812376), Stewarts Point (3812364)?, Tomales (3812228), Valley Ford (3812238)

Threat List Data from the CNDDB


Threat List Total:	6
EOs with Threat Listed:	Total EOs	% of EOs
	8	42 %
Development	4	21%
Foot traffic/trampling	4	21%
Road/trail construction/maint.	4	21%
Non-native plant impacts	3	15%
Recreational use (non-ORV)	2	10%
Grazing	1	5%

Notes



Does plant occur in MRN Co.? Collection from 485C is intermediate with ssp. malviflora. Need quads for SMT Co. See University of Washington Publications in Biology 18:23 (1957) for original description.
Threats:
Threatened by development and non-native plants.
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 10 May 2025].