Water chestnut is an invasive aquatic plant with rosettes of triangular leaves that float on the water’s surface. It grows in the Bird and Sassafras rivers, which are tributaries of the upper Chesapeake Bay.
The water chestnut's triangular or diamond-shaped leaves form rosettes that float on the water’s surface. The leaves have teeth along the edges, a shiny upper side and fine hairs underneath. Thread-like leaves grow alternately along the submerged part of the stem. Tiny, white flowers bloom in June to July. Hard, greenish-brown fruits with four sharp spikes are attached to the plant’s underside in spring and early summer. Water chestnut can float freely or be rooted to bottom sediments.
Grows in muddy, fine-grained sediments in slow-moving fresh and brackish rivers.
Maryland’s Bird and Sassafras rivers.
Water chestnut can reproduce both sexually and asexually. Sexual reproduction takes place in early summer. After being fertilized, female flowers mature into fruit-bearing shoots. The shoots eventually break off, releasing their seeds as they float on the surface. Asexual reproduction takes place when the rhizome grows and winter buds, called "turions," form.