Zannichellia palustris L.
horned pondweed
Potamogetonaceae (Horned pondweed family)
(Previously in Zannichelliaceae)

Introduction to Vascular Plants

Photograph

© Mike Russum     (Photo ID #65715)


Map

E-Flora BC Static Map

Distribution of Zannichellia palustris
Click here to view the full interactive map and legend

Species Information

General:
Perennial, aquatic herb from slender rhizomes; stems threadlike, freely branching, 20-50 cm long.
Leaves:
Stem leaves opposite, threadlike, 1-nerved, 2-10 cm long, less than 1 mm wide, the tips abruptly pointed, membranous-sheathing at the base.
Flowers:
Inflorescence of male and female flowers in the axils, sometimes not together; the female flowers mostly of 3-5 carpels, unstalked or short stalked with a subtending bract shorter than the pistils; male flowers a single stamen.
Fruits:
Achenes, stalked, the backs curved, the fronts smooth or sharply toothed, beaked, the beaks 1 mm long.

SourceThe Illustrated Flora of British Columbia

Illustration

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Ecology

Ecological Framework for Zannichellia palustris

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class

Avg

Min

Max

Elevation (metres)
843 676 1010
Slope Gradient (%)
1 0 3

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

0
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
7 7 7
Modal Nutrient Regime
Class
D
# of field plots
 species was recorded in:
2
Modal BEC Zone Class
IDF

All BEC Zones (# of stations/zone) species was recorded in

BG(1), IDF(1)

Habitat and Range

Shallow, often alkaline or brackish lakeshores, slow-moving streams and tidal marshes in the lowland, steppe and montane zones; frequent in BC south of 54 degrees N, less frequent northward and on Vancouver Island; cosmopolitan, E to NF and NS and S to FL, TN, TX, MX; S America, Eurasia, Africa.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Zannichellia major (Hartm.) Boenn. ex Rchb.
Zannichellia palustris var. major (Hartman) W.D.J. Koch
Zannichellia palustris var. stenophylla Aschers. & Graebn.