Taxon Report

Poa napensis Beetle

Napa blue grass

Print Report

Taxon Summary

Poa napensis, commonly known as Napa blue grass, is a perennial herb in the Poaceae that is found only in California. It occurs within Meadows and seeps, and Valley and foothill grassland, growing at elevations from 100 to 200 meters. Poa napensis is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

Classification


Scientific Name:	Poa napensis Beetle
Common Name:	Napa blue grass
Family:	Poaceae
Element Code:	PMPOA4Z1R0
USDA Plants Symbol:	PONA
Synonyms/Other Names:

Ecology and Life History


Lifeform:	perennial herb
Blooming Period: May-Aug	May-Aug
Elevation:	100-200 (330-655)
General Habitats:	Meadows and seeps, Valley and foothill grassland
Microhabitat:	Alkaline
Microhabitat Details:	near thermal springs

Conservation Status


CA Rare Plant Rank:	1B.1
Global Rank:	G1
State Rank:	S1
State List:	CE
Fed List:	FE
Other Status:	SB_CalBG/RSABG
CRPR Changes:

Occurrence Data from the CNDDB


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

Location


California Endemic: True
California Counties and Islands: Name (Code)
Napa (NAP)
Quads: Name (Quad Code)
Calistoga (3812255)

Threat List Data from the CNDDB


Threat List Total:	7
EOs with Threat Listed:	Total EOs	% of EOs
	2	100 %
Development	2	100%
Foot traffic/trampling	2	100%
Grazing	1	50%
ORV activity	1	50%
Other	1	50%
Road/trail construction/maint.	1	50%
Surface water diversion	1	50%

Notes



Known from only two occurrences in the Calistoga area. Threatened by development, hydrological alterations, recreational activities, and airport maintenance. See Leaflets of Western Botany 4:289 (1946) for original description.
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 4 November 2025].