The flowering rush (butomus umbellatus) is not actually a rush at all. It is very beautiful but it has become a serious invasive weed in the Great Lakes. I don’t know if it is considered to be an invasive weed in this area but I intend to find out because I know where there are two stands locally. One is in a little creek that runs into Graham Creek in Andrew Hayden park and the other is on a marshy part of the shore near the NCC trail.
It grows in still and slowly moving water to a depth of three metres. It has linear, pointed leaves that are about a metre long, they grow in two rows from the rhizome base. The inflorescence is umbel like (like an upside down umbrella) and each little flower has three pink petals with darker veins. They flower from July to August.