It smells like licorice, why fragrant waterlily is one of its common names. In spring the leaves and flowers rise to the surface of shallow, calm waters. The flowers open in morning, and close late in the day. Beavers take nips from the closed blooms.
The plant is native to eastern North America. It spreads by seed, and rhizome. The leaves can cover large areas of open water, excluding other plants and creating stagnant zones with low oxygen levels. The entangling stems, one to two metres long, seem to have evolved to wrench canoe paddles from the unwary.
It has been introduced to southern British Columbia, including into Burnaby Lake, a small, post-glacial lake in the City of Burnaby, Vancouver's eastern neighbour. The lake is fed by several urban streams, and is drained by the Brunette River, which eventually meets the Fraser River.
The once swimmable, sailable lake has become clogged with sediments, including silt from natural run-off, sawmill discards, storm sewer miscellanea, industrial pollution, and, increasingly, decomposing plant material. Nymphaea found a place to thrive and spread--and alter as it spreads, providing shallower, stiller water for more of its kind. Open water in the lake is largely restricted to a long rectangle that runs down the centre --rowing lanes that were established through dredging more than 30 years ago.
(The smaller lake in the bottom left is Deer Lake.)
For years, there has been discussion of further dredging, both to maintain the condition of the rowing lanes, and, to some extent, to reestablish the natural environment of the lake. It is not a simple task. There is a great deal of muck to be removed, and much of it is significantly contaminated with industrial toxins.
According to this source, dredging will commence in September. Priority, the rowing lanes.
Lean from your shell, pluck a lily, and smell the licorice.