CNPS

CNPS Rare Plant Inventory



Taxon Details

Layia septentrionalis

Colusa layia

  View Report   Copy Link Calflora eFlora CCH CalPhotos iNaturalist
Photo of Layia septentrionalis
© 2013 Jake Ruygt 		Photo of Layia septentrionalis
© 2020 Zoya Akulova 		Photo of Layia septentrionalis
© 2013 Jake Ruygt

Taxon Summary:

Layia septentrionalis, commonly known as Colusa layia, is a annual herb in the Asteraceae that is found only in California. It occurs within Chaparral, Cismontane woodland, and Valley and foothill grassland, growing at elevations from 100 to 1095 meters. Layia septentrionalis is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

  Classification

Scientific Name:
Layia septentrionalis Keck
Common Name:
Colusa layia
Family: Asteraceae
Element Code: PDAST5N0F0
USDA Plants Symbol: LASE2
Synonyms/Other Names:
Name Status: JEF, FNA, POWO,
IPNI, Tropicos

  Conservation Status

CA Rare Plant Rank: 1B.2
Fed List: None
State List: None
Global Rank: G2
State Rank:
 S2
Other Status: BLM_S; SB_UCBG
CRPR Changes:
Add Date: 1994-01-01
Date Edited: 2022-03-01

  Ecology and Life History

Lifeform: annual herb
Blooming Period: Apr-May
JFMAMJJASOND
Elevation:
100 - 1095 meters
330 - 3595 feet
General Habitats:
  • Chaparral
  • Cismontane woodland
  • Valley and foothill grassland
Microhabitat Details:
Microhabitat:
  • Sandy
  • Serpentine

  Notes

Notes:
Historical occurrences need field surveys.
Threats:

Threatened by development.
Taxonomy:

  Threat List Data from the CNDDB

Threat List Total: 7
Total EOs % of EOs
EOs with Threat Listed: 10 14 %
THREAT LIST:
Road/trail construction/maint. 5 7%
Development 3 4%
Erosion/runoff 1 1%
Grazing 1 1%
Other 1 1%

  Occurrence Data from the CNDDB

Total Occurrences: 69
Element Occurrence Ranks:
A B C D X U
7 7 0 0 1 54
Occurrence Status:
Historical >20 Years 46
Recent <=20 Years 23
Presence:
Presumed Extant 68
Possibly Extirpated 1
Presumed Extirpated 0

  Location

California Endemic:
California Island:
States: Name (Code)
California (CA)
California Counties and Islands: Name (Code)
Butte (BUT), Colusa (COL), Glenn (GLE), Lake (LAK), Mendocino (MEN), Napa (NAP), Sonoma (SON), Sutter (SUT), Tehama (TEH), Yolo (YOL)
Quads: Name (Quad Code)
Aetna Springs (3812264), Arbuckle (3912211), Benmore Canyon (3912215), Cherokee (3912165), Chiles Valley (3812253), Cloverdale (3812371), Detert Reservoir (3812265), Dunnigan (3812188), Elk Creek (3912255), Gilmore Peak (3912235), Glascock Mtn. (3812283), Grimes (3912118), Highland Springs (3812288), Hopland (3812381), Jericho Valley (3812274), Kelseyville (3812287), Kenwood (3812245)*, Knoxville (3812273), Lakeport (3912218), Leesville (3912224), Lower Lake (3812285), Lucerne (3912217), Monticello Dam (3812251), Paskenta (3912285), Purdys Gardens (3912311), Rail Canyon (3912244), Riley Ridge (3912286), Rumsey (3812282), Santa Rosa (3812246), St. Helena (3812254), Stonyford (3912245), Sutter Buttes (3912127), The Geysers (3812277), Walter Springs (3812263), Whispering Pines (3812276), Wilbur Springs (3912214), Wildwood School (3812281), Wilson Valley (3812284)
Notes:
Definitions of codes following a county and/or quad:
* Presumed extirpated
(?) Occurrence confirmed, but possibly extirpated
Quad and county data is imported from the CNDDB. Species may be present in other areas where conditions are favorable. These data should NOT be substituted for pre-project review or for on-site surveys.
Regional Map

  Map

Presumed Extant
Click on quad for name. Hold Shift Key to use mouse scroll wheel

  Selected References

Original Description: Aliso 4(1):106 (1958)
Species Account: Layia septentrionalis profile for potential Species of Conservation Concern evaluation (2018)
Other: USFS Potential Species of Conservation Concern Profile

Go to top


Suggested Citation:
California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 26 January 2025].
}