SASK Herbarium Rareplants Virtual Herbarium Rareplants Virtual Herbarium
Researcher Enthusiast Youth My Plant
  Home Contact Us Sitemap French
 
Back to: Plants at Risk in Saskatchewan
Myriophyllum pinnatum (Walt.) B.S.P.
Species Image Gallery
(opens in a new window)
 
TAXONOMY
 
Family: Haloragaceae
Genus: Myriophyllum
 
Species Synonyms: Myriophyllum scabratum Michx.
Potamogeton pinnatum Walt.
Myriophyllum verticillatum var. cheneyi Fassett
Common Names: cutleaf watermilfoil
green parrot’s feather
pinnate water-milfoil
 
DISTRIBUTION
 
Canada: southeastern Saskatchewan, southwestern Ontario
Saskatchewan: southeastern Saskatchewan
Ecoregion: Moist Mixed Grassland
 
HABITAT
 
Saskatchewan: shallow sloughs
 
RARITY STATUS
 
Provincial Status According
to Harms (2003):
Endangered/Extirpated?
Nature Conservancy Status:
G5 S1
Saskatchewan Species at
Risk Status:
None
COSEWIC Status:
None
 
Myriophyllum pinnatum is endangered or possibly even extirpated from Saskatchewan. This plant is extremely rare and is known only from one location and its existence in the province has not been verified for at least 50 year.
 
SPECIES DESCRIPTION
 
Height: rhizomes
Stems: perennial, aquatic, 30 – 150 cm long, branches simple to spreading
Leaves: submersed leaves whorled in groups of 3 – 6, 0.7 – 3.0 cm long, flaccid, with 3 – 5 pairs of thread-like divisions; emersed leaves linear and narrow, longer than flowers, upper leaves rigid, irregularly pinnatifed to shallowly toothed
Inflorescence: spikes emersed, axillary, 10 – 20 cm long, 4 – 6-flowered; staminate flowers above, pistillate below; lowermost bracts grading into leaves
Flowers: flowers perfect or unisexual; calyx 4-merous, purplish; corolla 4-merous, purplish; stamens 4; ovary inferior
Fruits: nut-like, deeply 4-lobed, subglobose, pale
 
MYRIOPHYLLUM KEY FOR SPECIES FOUND IN SASKATCHEWAN
 
1 Flowers in axils of submersed or emersed leaves; stamens 4
M. pinnatum
1 Flowers in a terminal spike; stamens 8
2
   
2 Low, single stemmed plant; leaflets toothed or entire, greater than 3 cm long; fruits white and smooth
M. alterniflorum
2 Floral bracts opposite or whorled; submersed leaves with up to 11 pairs of capillary divisions
3
 
3 Emersed leaves reduced, bract-like, upper leaves entire, lower serrate; leaf whorls greater than or equal to 1 cm apart
M. sibiricum
3 Emersed leaves pinnatifed, margins pectinate, serrate or entire; leaf whorls less than 1 cm apart
4
 
4 Floral bracts shorter than or equal to fruits, margin serrate to entire
M. verticillatum
4 Floral bracts usually surpassing the fruits, margin serrate to pectinate
M. spicatum