One of the most important characteristics of any biome is its plant life or lack of plant life. More than 5,000 species of plants live in or near wetlands. Wetlands have high biological productivity (the rate at which life forms grow in a certain period of time). The higher its plant productivity, the more animal life a wetland can support. The kinds of plants that may be found in a wetland are determined by several factors, especially the type of soil and the quantity of water.

Some plants, called hydrophytes, grow only in water or extremely wet soil. Sedges are an example. Mesophytes, such as reeds, need moist but not saturated soil. When a wetland dries up, the area fills with plants called xerophytes. These are plants adapted to life in dry habitats and can survive where other wetland plants would wilt. They include water hemp, marsh...