E-Flora BC: Electronic Atlas of the Flora of British Columbia

Myriophyllum ussuriense (Regel) Maxim.
Ussurian water-milfoil (Russian water-milfoil)
Haloragaceae (Water Milfoil family)

Introduction to Vascular Plants

© Frank Lomer  Email the photographer   (Photo ID #27801)

E-Flora BC Static Map
Distribution of Myriophyllum ussuriense
Click here to view the full interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Introduction

According to Ceska and Ceska (2010), this is an "Amphiberingian species, Far East of Asia and British Columbia, Washington and Oregon. Dioecious, population clonal, usually of one sex (female populations prevailing) some populations rarely with hermaphroditic individuals. Terrestrial or semiterrestrial at the margins of lakes and rivers with fluctuating water table, truly aquatic plants rare. Habit is unlike of any other our milfoil. Winter buds inconspicuous, filiform."

Species Information

Click on the image below to view an expanded illustration for this species.



General:
Perennial aquatic or semiterrestrial from a rhizome, stems up to 25 cm tall.
Leaves:
Emergent leaves opposite or in whorls of 3, 1-8 mm long, linear or lanceolate in outline, entire or pinnate with 1-3 pairs of segments; submersed leaves in whorls of 3, pinnate, broadly egg-shaped in outline, with 2-4 (7) alternate segments on each side; winter buds 3-7 mm long, threadlike, formed in the leaf axils.
Flowers:
Male and female flowers developed on separate plants (plants dioecious) in the axils of the floral bracts; floral bracts similar to the leaves, usually entire, or with a few stubby segments on each side; male flowers with soon deciduous white petals about 3 mm long; stamens 8, deciduous; female flowers inconspicuous, greenish, with four feather-like stigmas.
Fruits:
Were not observed in BC.
Notes:
Most populations of this species in British Columbia have only female plants; male populations are known from the lower Fraser River valley.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Lake margins and muddy river banks in the lowland zone; rare on Vancouver Island, lower Fraser River valley and SE BC; amphiberingian, in North America known only from BC, WA and OR; China, Primor'ye, Kamchatka, Japan.

Source: The Illustrated Flora of British Columbia

Climate

The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Taxonomic and Nomenclatural Links

Additional Photo Sources

Species References

Ceska, Oldriska and Adolf Ceska. 2010. Genus Myriophyllum (Haloragaceae) in the Pacific Northwest. Botanical Electronic News #428. Available online.

General References