Taxon Report

Potamogeton foliosus Raf. ssp. fibrillosus (Fern.) R. R. Haynes & Hellq.

fibrous pondweed

Print Report

Taxon Summary

Potamogeton foliosus ssp. fibrillosus, commonly known as fibrous pondweed, is a perennial rhizomatous herb (aquatic) in the Potamogetonaceae that is found in California and elsewhere. It occurs within Marshes and swamps, growing at elevations from 5 to 1300 meters. Potamogeton foliosus ssp. fibrillosus is ranked 2B.3, Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere; Not very threatened in California.

Classification


Scientific Name:	Potamogeton foliosus Raf. ssp. fibrillosus (Fern.) R. R. Haynes & Hellq.
Common Name:	fibrous pondweed
Family:	Potamogetonaceae
Element Code:	PMPOT030B1
USDA Plants Symbol:	POFOF5
Synonyms/Other Names:	Potamogeton foliosus Raf. var. fibrillosus (Fern.) R. Haynes & Rev.

Ecology and Life History


Lifeform:	perennial rhizomatous herb (aquatic)
Blooming Period: Unk	Unk
Elevation:	5-1300 (15-4265)
General Habitats:	Marshes and swamps
Microhabitat:
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	2B.3
Global Rank:	G5T2T3
State Rank:	S1S2
State List:	None
Fed List:	None
Other Status:
CRPR Changes:	changed from 2.3 to 2B.3 on 2013-06-12

Occurrence Data from the CNDDB


Total Occurrences:	1
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	1

Location


California Endemic: False
California Counties and Islands: Name (Code)
Del Norte (DNT)
Quads: Name (Quad Code)
Crescent City (4112472), Sister Rocks (4112462)

Threat List Data from the CNDDB


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

Notes



Known in CA from only one occurrence from Crescent City. To be expected in Great Basin areas of CA; need information. Endangered in OR. See Memoirs of the American Academy of Arts and Sciences 17(1):51 (1932) for original description, and Rhodora 75:76 (1973) for revised nomenclature and 76:564-649 (1974) for taxonomic treatment.
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 7 November 2025].