Gallery:
Common names:
Flowering rush, grass rush, water gladiolus
Scientific Name:
Butomus umbellatus
Description:
Flowering rush is an aquatic perennial plant in the Butomaceae family. Leaves are thin, and either straight or slightly twisted, up to 40 inches long, and have a triangular cross-section at the base. When the plant is submerged the leaves are flexible, and when emerging along the shoreline, they are more stiff. Flowers have 3 large pink petals (with three sepals below that look like petals), and grow in flat-topped clusters of 20-50 on tall cylindrical stalks. It has fleshy rhizomes that trail along the ground (??). It was introduced as an ornamental and is sometimes still sold for water gardens. It spreads mostly through rhizome fragments or small bulbils that detach and disperse through the water, though some varieties also produce seeds.
Life cycle:
Height of mature plants
Up to 5 feet
Flower color:
Light pink
Bloom time:
June – August
Look-a-likes:
While not a true rush, it looks similar to many other rushes and bulrushes
Habitat:
Flowering rush requires wet soil and sunshine. It can be found in wetlands, irrigation ditches, shorelines, and along slow-moving streams and rivers, and it can grow in water up to 9 feet deep. It often grows in areas with fluctuating water levels and can tolerate a wide variety of temperatures.
Impacts:
Flowering rush is an aggressive colonizer that can out-compete native wetland and shoreline vegetation. It can clog slow moving waterways and impede boat travel and fishing along shoreline, thus degrading both their recreational and ecological value. As an aquatic plants that spreads vegetatively, it is difficult to control, and can be easily spread by waterfowl, wildlife, and boaters.
Noxious Weed Listing:
- WeedWise: priority
- State of Oregon: Class A, T
- State of Washington: Class A
- Four County CWMA: Class W
- Columbia Gorge CWMA: Class A
Origin:
Northern Africa, Asia, and Europe
Links:
Oregon Noxious Weed Profile
Washington Noxious Weed Profile
King County Noxious Weed Profile
Invasive.org profile