Native to North America, and widely distributed from Ohio and Texas to the west coast.
An aquatic annual that grows in marshy areas or at the edges of ponds, ditches, or streams. It also is a problem weed in rice fields. Reproduction is from seeds.
Mature plants may be as tall as 2 feet as sparse plants composed of long, narrow stems that terminate with the flower clusters, and long leaf stalks terminating in the oval or heart-shaped leaves, all of these stems and stalks arising from the base. Leaves may be up to 8 inches long, but their stalks are usually much longer than that. If the plants are growing in deep water the leaves become elongated and almost ribbon-like.
Flowers may be borne singly, or there may be branching of the upper stem to form numerous long, thin branches, along which the flowers occur. The flowers form as whorls on the stems, with the flower head composed of three large green sepals and three large white petals. These result in the seed head, which is a large, bur-like, round pod up to ½ inch in diameter, with the seeds forming in the spiny burs.
Characteristicts Important to Control:
Very wet conditions are required for the growth of this plant. Individual plants may be removed by hand if done prior to seed maturation.