Potamogeton praelongus Wulfen
long-stalked pondweed (whitestem pondweed)
Potamogetonaceae (Horned pondweed family)

Introduction to Vascular Plants

Photograph

© Adolf Ceska     (Photo ID #11283)


Map

E-Flora BC Static Map

Distribution of Potamogeton praelongus
Click here to view the full interactive map and legend

Species Information

General:
Perennial, aquatic herb from strong rhizomes; stems mostly unbranched, often flexuous, nearly circular in cross-section, tapered, up to 200 cm long.
Leaves:
All submersed, linear-lanceolate, thin, flat, light green fading to white, 10-20 cm long, 2-4 cm wide, with 11 to 33 veins, clasping the stem, the tips rounded or hood-shaped, the stipules 3-10 cm long, fibrous or stringy; floating leaves absent.
Flowers:
Inflorescence spikelike, the spikes 3-5 cm long, with 6 to 12 whorls of flowers, the stalks inflated.
Fruits:
Achenes, widely egg-shaped or almost globe-shaped, 4.3-5.7 mm long, 3.2-4 mm wide, the beaks prominent, widely triangular, the keels wide.
Notes:
Stem anatomical characters interlacunar bundles throughout the stem aerenchyma, subepidermal bundles absent, pseudohypodermis 1 to 3 cells thick, endodermis of U-cells.

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.

USDA Species Characteristics

Flower Colour:
Green
Blooming Period:
Late Spring
Fruit/Seed characteristics:
Colour: Green
Present over the Summer
Source:  The USDA

Ecology

Ecological Framework for Potamogeton praelongus

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)
Slope Gradient (%)

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

0
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
Modal Nutrient Regime
Class
# of field plots
 species was recorded in:
1
Modal BEC Zone Class
CWH

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

CWH(1)

Habitat and Range

Lakes in the lowland, steppe and montane zones; frequent throughout BC; circumpolar, N to AK, YT and NT, E to NF and S to ME, MA, NY, OH, IN, IL, IA, NE, CO, UT, ID and CA; Eurasia.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Potamogeton praelongus var. angustifolius Graebn.