Plants
Here are just a few aquatic plants:
Water Lilies are found in all still and slow-flowing freshwaters. One thing that I have noticed about them is that on any lake or pond, you will always find white ones, and usually also pink or yellow ones, but never both. The flowers begin in summer and last well into fall.
More: Water Lilies ...
Fanwort
Fanwort is a fully aquatic true plant. It grows steadily through the warm months, and can choke-out large areas, then dies back in the winter. Fanwort produces tiny flowers above the surface.
More: Fanwort & Hornwort ...
Sedges and Reeds are superficially similar, but actually quite different. But unless you are a biologist - who cares? ( Reeds are grasses, sedges are sedges. )
Sedges
Sedges tolerate a wide range of salinity, from freshwater to seawater, although they seem to grow best in brackish water. So, like above, if you are exploring a bay or inlet, that stuff all around you is most likely sedge.
More: Sedges & Reeds ...
Kayaking is an outdoor activity. Yes, kids, you'll have to put down your game controllers and go outside. Out there is what us older folks call nature. Nature can actually be quite beautiful and interesting, and you don't have to worry about your screen resolution and refresh rate - both are infinity. So here is a short list of flora and fauna ( plants and animals ) that you might see in freshwater environments:
More: Wildlife ...