Species Details

Polygonum bidwelliae

Bidwell's knotweed

Download Report Calflora eFlora CCH CalPhotos

Classification

Scientific Name: Polygonum bidwelliae Wats.
Common Name: Bidwell's knotweed
Family:	Polygonaceae
Element Code:	PDPGN0L0C0
USDA Plants Symbol:	POBI4
Synonyms/Other Names:

Conservation Status

CA Rare Plant Rank:	4.3
Fed List:	None
State List:	None
Global Rank:	G4
State Rank:	S4
Other Status:
CRPR Changes:
Add Date:	1974-01-01
Date Edited:	2022-06-08

Ecology and Life History

Lifeform: annual herb

Blooming Period: Apr-Jul

Elevation:
60 - 1200 meters
195 - 3935 feet

General Habitats:

Chaparral
Cismontane woodland
Valley and foothill grassland

Microhabitat Details:

Microhabitat:

Volcanic

Notes

Notes: Possibly threatened by vehicles, foot traffic, soil erosion, and non-native plants. See Proceedings of the American Academy of Arts and Sciences 14:294 (1879) for original description.
Threats:
Taxonomy:

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)

California Counties and Islands: Name (Code)
Butte (BUT), Shasta (SHA), Tehama (TEH)

Quads: Name (Quad Code)
Acorn Hollow (4012118), Barkley Mtn. (4012126), Bend (4012232), Burney (4012186), Burney Falls (4112116), Campbell Mound (3912187), Cherokee (3912165), Cohasset (3912186), Dales (4012231), Devils Parade Ground (4012116), Dewitt Peak (4012128), Finley Butte (4012137), Hagaman Gulch (4012157), Inwood (4012158), Los Molinos (4012211), Manton (4012147), Panther Spring (4012127), Paradise East (3912175), Paradise West (3912176), Richardson Springs (3912177), Shippee (3912156), Tuscan Buttes Ne (4012241), Tuscan Springs (4012221)

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

CNPS Rare Plant Inventory