Flowering rush has been spotted in a few locations in Alberta, including an infestation on Lake Isle, located in Lac St. Anne and Parkland counties.
Flowering rush is a perennial of freshwater wetlands that is native to Africa, Asia and Europe and was introduced to North America as an ornamental plant species. It is a prohibited noxious weed, which means it is to be destroyed whenever it is found. It can spread by seed or root fragments so care must be taken with attempts to remove existing plants. It can displace natural vegetation and reduce water quality which may disrupt valuable fish and wildlife habitat.
Flowering rush has triangular stems, sword-shaped leaves, and flowers vary from pink to white in umbrella-shaped clusters.
Control of this weed is extremely difficult. Mechanical control can suppress the plant but will need to be repeated and all parts of the plant must be removed and disposed of in a landfill. Currently no herbicides are registered for use on flowering rush, and applications near water require specific applicator certificates and permits from Alberta Environment and Parks.
By Erin McAdam, Supervisor Agricultural operations, Parkland County