Plant Life in Wetlands

Marshes

• Marshes can be likened to wet prairies. Marshes form in bottomlands and depressed areas of upland prairies. Marsh plants are soft-stemmed and thrive in saturated soil. Sediment and pollutants from fertilizer run-off settle in marshes and the plants clean the water by using the excess nutrients. Emergent vegetation, such as reeds, bulrushes, cattails, and grasses dominates this type of wetland. The soil may be covered with water or saturated with water for much of the year. Some marshes drain for much of the growing season.

Swamps

• Swamps are forested wetlands. Cypress and tupelo trees dominate southern swamps; red maple and pin oak trees grow in the Northeast; hemlock trees grow in the Northwest. These are deep-water wetlands where soil is covered by 12 inches to several feet of water. Shrub swamps are shallower; the ground is covered with approximately six inches of water. Dogwood, willow and alder trees and button bushes are common plants in shrub swamps.

Bogs

• Bogs are wetlands that depend on precipitation to maintain their water supply to provide nutrients. The dominant plant, sphagnum moss, forms a dense, spongy mat atop the water level. Bogs are low in mineral salts and pH. This acidic, nutrient-poor environment favors carnivorous plants, such as the pitcher plant, which obtains nutrients from insects it traps in its water-filled leaves. Pocosins are southern, upland bogs with acidic, low-nutrient water. Evergreen trees and shrubs dominate these bogs from Virginia down the Atlantic coast to northern Florida.

Fens

• Partially decayed organic matter accumulates in wetlands called fens. The decaying material helps to retain water in the fen. Fens are similar to bogs, but in addition to precipitation, they receive water from groundwater and other sources. The additional water source raises the pH and makes the water in fens less acidic than bogs. As a result, fens support a wider variety of plants than bogs. The dominant plant life is sedges, grasses, rushes, wildflowers and other types of herbaceous plants.