Ceratophyllum demersum L.
common hornwort (coon's tail; coontail)
Ceratophyllaceae (Hornwort family)

Introduction to Vascular Plants

Photograph

© Royal BC Museum (Tom Armstrong)     (Photo ID #2217)


Map

E-Flora BC Static Map

Distribution of Ceratophyllum demersum
Click here to view the full interactive map and legend

Species Information

General:
Aquatic herb, usually without roots; stems freely branching, 0.3-4.0 m long.
Leaves:
Stem leaves submerged, in whorls of 5-12, 2-3 times forked into linear or threadlike segments, these often stout, stiff and spiny-toothed.
Flowers:
Inflorescence of solitary, minute, axillary flowers; petals lacking; sepals 3-15, sometimes petal-like; stamens 12-16.
Fruits:
Achenes usually lacking, if present then much flattened, 4-6 mm long, ellipsoid, wingless with a persistent style and 2 basal spines.

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:
Blue
Blooming Period:
Summer
Fruit/Seed characteristics:
Colour: White
Present from Summer to Fall
Source:  The USDA

Ecology

Ecological Framework for Ceratophyllum demersum

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)
1067 840 1118
Slope Gradient (%)
0 0 1

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

300 301 301
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
7 7 8
Modal Nutrient Regime
Class
B
# of field plots
 species was recorded in:
14
Modal BEC Zone Class
SBPS

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

CDF(3), CWH(2), ICH(1), IDF(1), SBPS(7)

Habitat and Range

Ponds, lakes and slow-moving streams in the lowland, steppe and montane zones; common in S BC, less frequent northwards; N to AK, YT and NT, E to PQ, NS and NB and S to FL, TX, CA and MX.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Ceratophyllum apiculatum Cham.
Ceratophyllum demersum var. apiculatum (Cham.) Asch.
Ceratophyllum demersum var. apiculatum (Cham.) Garcke