Swamps are forested wetlands which may have a groundcover of ferns, grasses, sedges or rushes. Usually found along the margins of lakes, streams and bogs, they are seasonally dry. Bogs are distinguished from other wetlands by the presence of sphagnum moss. They are primarily upland freshwater wetlands and usually occur as a result of natural infilling of a lake or pond by sediment. In their later stages, they may support black or white spruce.
Fens are inland, freshwater marshes common in lime-rich areas.
Both coastal and inland wetlands provide multi-use potential for hunting, fishing and recreation. Converting them to single use, such as draining for agricultural use, for instance, may diminish the total value of multiple use. The fact that the economic value of wetlands is difficult to measure on a balance sheet may account for the low priority which wetlands protection policy has been accorded in the past. Perhaps one simple way to measure the value of wetlands is to consider the cost of losing them. If, for example, your well goes dry because of the loss of an upslope reservoir of groundwater, there are a number of alternatives open to you.