Taxon Details

Iris thompsonii

Thompson's iris

View Report Copy Link Calflora eFlora CCH CalPhotos iNaturalist

Taxon Summary:

Iris thompsonii, commonly known as Thompson's iris, is a perennial rhizomatous herb in the Iridaceae that is found in California and elsewhere. It occurs within Lower montane coniferous forest, and North Coast coniferous forest, growing at elevations from 90 to 600 meters. Iris thompsonii is ranked 4.3, Plants of Limited Distribution, A Watch List; Not very threatened in California.

Classification

Scientific Name: Iris thompsonii R.C. Foster
Common Name: Thompson's iris
Family:	Iridaceae
Element Code:	PMIRI09120
USDA Plants Symbol:
Synonyms/Other Names:
Name Status:	JEF, FNA, POWO, IPNI, Tropicos

Conservation Status

CA Rare Plant Rank:	4.3
Fed List:	None
State List:	None
Global Rank:	G3
State Rank:	S3
Other Status:
CRPR Changes: added to 4.3 on 2018-07-24
Add Date:	2021-07-24
Date Edited:	2022-03-01

Ecology and Life History

Lifeform: perennial rhizomatous herb

Blooming Period: (Mar-Apr)May-Jun(Jul-Aug)

Elevation:
90 - 600 meters
295 - 1970 feet

General Habitats:

Lower montane coniferous forest
North Coast coniferous forest

Microhabitat Details:

Microhabitat:

Edges (often)
Mesic (usually)
Openings
Roadsides (sometimes)
Serpentine (often)
Streambanks (sometimes)

Notes

Notes:
Threats:
Taxonomy: Considered to be a hybrid of I. douglasiana and I. innominata in OR.

Threat List Data from the CNDDB

THREAT LIST:
Threat List Total:	0
	Total EOs	% of EOs
EOs with Threat Listed:	0	0 %

Occurrence Data from the CNDDB

Element Occurrence Ranks:
Total Occurrences:					0
A	B	C	D	X	U
0	0	0	0	0	0

Occurrence Status:
Historical >20 Years	0
Recent <=20 Years	0

Presence:
Presumed Extant	0
Possibly Extirpated	0
Presumed Extirpated	0

Location

California Endemic:

California Island:

States: Name (Code)
California (CA), Oregon (OR)

California Counties and Islands: Name (Code)
Del Norte (DNT), Siskiyou (SIS)

Quads: Name (Quad Code)
Broken Rib Mtn. (4112386), Cant Hook Mtn. (4112368), Gasquet (4112378), Happy Camp (4112374), Hiouchi (4112471), Hurdygurdy Butte (4112377), Klamath Glen (4112358), Shelly Creek Ridge (4112387)

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

CNPS Status Review:	Proposed Addition to California Rare Plant Rank 4.3, G3 / S3
Original Description:	Rhodora 38(450):199-201 (1936)
Taxonomic Treatment:	Madroño 37(2):113-123 (1990)
Species Account:	Iris thompsonii profile for potential Species of Conservation Concern evaluation (2018)
Other:	USFS Potential Species of Conservation Concern Profile
Other:	Aliso 4:1-72 (1958) [Hybrid Taxonomic Treatment]
Other:	Journal of Botany 83(12):1623-1629 (1996) [Hybrid Taxonomic Treatment]

Go to top