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

Butomus umbellatus L.
Butomaceae (Flowering Rush family)

Introduction to Vascular Plants

© Bruce Bennett  Email the photographer   (Photo ID #22939)

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


Flowering rush is an introduced species in North America that originates in Eurasia, and was brought to North America as an ornamental plant in water gardens. It is now found across the northern US states from Idaho to Vermont, and in Canada (AB, BC, MB, NB, NS, ON, PE, QC) (USDA 2010). While it is often rare in its native range, it has become a serious pest where it is introduced, including in the Great Lakes area. In British Columbia, it is known from only two locales: Hatzic Lake near Mission and a single location in Surrey, on West Creek, and may be more frequent but overlooked. This is a distinctive flowering plant species. It is a relatively tall (100-150 cm) rhizomatous (thick rhizomes) perennial that is rush-like in appearance (narrow leaves) with an umbel of pink flowers. It inhabits shorelines but can tolerate deeper water to depths of 2 m (Global Invasive Species Database 2010). It flowers through the summer from June to August.

Species Information

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

Perennial aquatic herb from a stout rhizome; stems solitary, 100-150 cm tall.
All basal, erect or floating in deep water, linear, twisted, 50-100 cm long, 0.5-1 cm wide.
Inflorescence of numerous flowers on slender stalks in an umbel; perianth 2-2.5 cm wide, long-stalked, the stalks 5-10 cm long, subtended by narrowly triangular bracts; petals 3, pink, more deeply coloured on the outside; sepals 3, greenish outside along the midribs, nearly as long as the petals; stamens 9.
Follicles, 6, beaked, about 1 cm long; seeds straight, lined.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Marshes and lakeshores; rare in SW BC, known only from Hatzic Lake; introduced from Eurasia.

Source: The Illustrated Flora of British Columbia


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

General References