Taxon Report

Trichostema ruygtii H. Lewis

Napa bluecurls

Print Report

Taxon Summary

Trichostema ruygtii, commonly known as Napa bluecurls, is a annual herb in the Lamiaceae that is found only in California. It occurs within Chaparral, Cismontane woodland, Lower montane coniferous forest, Valley and foothill grassland, and Vernal pools, growing at elevations from 30 to 680 meters. Trichostema ruygtii is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Trichostema ruygtii H. Lewis
Common Name:	Napa bluecurls
Family:	Lamiaceae
Element Code:	PDLAM220H0
USDA Plants Symbol:	TRRU11
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Jun-Oct	Jun-Oct
Elevation:	30-680 (100-2230)
General Habitats:	Chaparral, Cismontane woodland, Lower montane coniferous forest, Valley and foothill grassland, Vernal pools
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.2
Global Rank:	G2
State Rank:	S2
State List:	None
Fed List:	None
Other Status:	SB_CalBG/RSABG
CRPR Changes:	changed from 4 to 1B.2 on 2009-06-08 added to 4 on 2007-01-03

Occurrence Data from the CNDDB


Total Occurrences:	19
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	1
Poor (D)	0
None (X)	2
Unknown (U)	16

Location


California Endemic: True
California Counties and Islands: Name (Code)
Lake (LAK), Napa (NAP), Solano (SOL)
Quads: Name (Quad Code)
Capell Valley (3812242), Detert Reservoir (3812265), Highland Springs (3812288), Kelseyville (3812287), Mt. George (3812232), Napa (3812233), St. Helena (3812254), Yountville (3812243)

Threat List Data from the CNDDB


Threat List Total:	2
EOs with Threat Listed:	Total EOs	% of EOs
	3	16 %
Agriculture	2	10%
Development	1	5%

Notes



Threatened by agriculture and development. See Madrono 53(3): 282 (2006) for original description.
Threats:

Taxonomy:

Selected References

CRPR List Addition on 2007-01-03

CRPR List Change on 2009-06-08

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 22 November 2025].