Species Details

Cirsium fontinale var. campylon

Mt. Hamilton thistle

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Species Description:

Cirsium fontinale var. campylon, commonly known as Mt. Hamilton thistle, is a perennial 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 890 meters. Cirsium fontinale var. campylon is ranked 1B.2, Plants Rare, Threatened or Endangered in California and Elsewhere; Moderately threatened in California.

Classification

Scientific Name: Cirsium fontinale Greene var. campylon (H.K. Sharsm.) Keil & C. Turner
Common Name: Mt. Hamilton thistle
Family:	Asteraceae
Element Code:	PDAST2E163
USDA Plants Symbol:	CIFOC
Synonyms/Other Names: Cirsium campylon H.L. Sharsm.
Name Status:	JEP, FNA, POWO, IPNI, Tropicos

Conservation Status

CA Rare Plant Rank:	1B.2
Fed List:	None
State List:	None
Global Rank:	G2T2
State Rank:	S2
Other Status:	BLM_S; SB_CalBG/RSABG
CRPR Changes:
Add Date:	1974-01-01
Date Edited:	2024-11-05

Ecology and Life History

Lifeform: perennial herb

Blooming Period: (Feb)Apr-Oct

Elevation:
100 - 890 meters
330 - 2920 feet

General Habitats:

Chaparral
Cismontane woodland
Valley and foothill grassland

Microhabitat Details:

Microhabitat:

Seeps
Serpentine

Notes

Notes: Threatened by urbanization, trampling, non-native plants, and grazing. Possibly threatened by recreational activities, and erosion. See Phytologia 73(4):312-317 (1992) for revised nomenclature.
Threats:
Taxonomy:

Threat List Data from the CNDDB

THREAT LIST:
Threat List Total:	13
	Total EOs	% of EOs
EOs with Threat Listed:	28	78 %
Grazing	12	33%
Non-native plant impacts	10	27%
Other	7	19%
Road/trail construction/maint.	7	19%
Development	5	13%
Foot traffic/trampling	5	13%
Erosion/runoff	4	11%
Landfill	4	11%
Recreational use (non-ORV)	2	5%
Biocides	1	2%
Surface water diversion	1	2%
Waterway bank protection/maintenance	1	2%
Wood cutting or brush clearing	1	2%

Occurrence Data from the CNDDB

Element Occurrence Ranks:
Total Occurrences:					36
A	B	C	D	X	U
6	17	4	0	0	9

Occurrence Status:
Historical >20 Years	16
Recent <=20 Years	20

Presence:
Presumed Extant	36
Possibly Extirpated	0
Presumed Extirpated	0

Location

California Endemic:

California Island:

States: Name (Code)
California (CA)

California Counties and Islands: Name (Code)
Alameda (ALA), Santa Clara (SCL), Stanislaus (STA)

Quads: Name (Quad Code)
Cedar Mtn. (3712155), Lick Observatory (3712136), Los Gatos (3712128), Morgan Hill (3712126), Mt. Boardman (3712144), Mt. Madonna (3712116), San Jose East (3712137), Santa Teresa Hills (3712127)

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

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CNPS Rare Plant Inventory