Duckweeds are pale green on both sides and generally elliptical in shape (1/10 - 1/8 inch long and less than 1/10 inch wide). The upper surface of the plant is keeled and bears a few papillae.
Most are aquatic carnivorous plants that lack true root systems. Bladderworts are composed of stems and branches. Bladders are present on all or a portion of the branches and stems. The bladders are used to capture small invertebrates, which are digested by enzymes.
These floating plants can grow as tall as 3 feet and sport leathery leaf blades that are elliptic and range from 1-8 inches in length. The root system is feathery and purplish to black in color. Water hyacinths have purple flowers.
Watermeal is the simplest and smallest of the flowering plants and appears as small green seeds.