Probes soft damp ground for insect larvae and worms. Takes off suddenly at your feet, flies straight up like a helicopter and darts and weaves through trees and bushes. Produce clusters of florets and lots of seed. Vary in height from a few inches to 2 or 3 feet. Have round stems, but not hollow.
Waterfowl eat seeds and roots.
Soft-stem bulrush has stout round stem, up to 8 feet tall. Ducks and geese eat seeds, geese root out tubers. This is a cover plant. Central stem with flowers and seeds. Underground runners give rise to tubers like a small potato.