Shrub swamps, also called
scrub swamps or
buttonbush swamps, are a type of
freshwaterFreshwater is naturally occurring water on the surface such as bogs, ponds, lakes, rivers and streams, and underground in aquifers and underground rivers. Freshwater is characterized by having low concentrations of dissolved salts...
wetlandA wetland is an area of land whose soil is saturated with moisture either permanently or seasonally. Such areas may also be covered partially or completely by shallow pools of water. Wetlands include swamps, marshes, and bogs, among others. The water found in wetlands can be saltwater, freshwater,...
ecosystemAn ecosystem is a system of interdependent organisms which share the same habitat, in an area functioning together with all of the physical factors of the environment. Ecosystems can be permanent or temporary. Ecosystems usually form a number of food webs...
occurring in areas too wet to become hardwood
swampA swamp is a wetland featuring temporary or permanent inundation of large areas of land by shallow bodies of water. A swamp generally has a substantial number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types...
s (“true” or forested swamps), but too dry or too shallow to become
marshIn geography, a marsh, or morass, is a type of wetland which is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, and other herbaceous plants. Woody plants will be low-growing shrubs. A marsh is different from a swamp,...
es. They are often considered transitional (“mid-successional”) between
wet meadowA wet meadow is a semi-wetland meadow which is saturated with water throughout much of the year. Wet meadows may occur because of poor drainage or the receipt of large amounts of water from rain or melted snow. They may also occur in riparian zones....
s or
fenA fen is a type of wetland fed by surface and/or groundwater. Fens are characterized by their water chemistry, which is neutral or alkaline...
s and conifer or hardwood swamps.
By some classifications, shrub swamps must have at least 50% shrub cover and less than 20% tree cover.
Shrub swamps, also called
scrub swamps or
buttonbush swamps, are a type of
freshwaterFreshwater is naturally occurring water on the surface such as bogs, ponds, lakes, rivers and streams, and underground in aquifers and underground rivers. Freshwater is characterized by having low concentrations of dissolved salts...
wetlandA wetland is an area of land whose soil is saturated with moisture either permanently or seasonally. Such areas may also be covered partially or completely by shallow pools of water. Wetlands include swamps, marshes, and bogs, among others. The water found in wetlands can be saltwater, freshwater,...
ecosystemAn ecosystem is a system of interdependent organisms which share the same habitat, in an area functioning together with all of the physical factors of the environment. Ecosystems can be permanent or temporary. Ecosystems usually form a number of food webs...
occurring in areas too wet to become hardwood
swampA swamp is a wetland featuring temporary or permanent inundation of large areas of land by shallow bodies of water. A swamp generally has a substantial number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types...
s (“true” or forested swamps), but too dry or too shallow to become
marshIn geography, a marsh, or morass, is a type of wetland which is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, and other herbaceous plants. Woody plants will be low-growing shrubs. A marsh is different from a swamp,...
es. They are often considered transitional (“mid-successional”) between
wet meadowA wet meadow is a semi-wetland meadow which is saturated with water throughout much of the year. Wet meadows may occur because of poor drainage or the receipt of large amounts of water from rain or melted snow. They may also occur in riparian zones....
s or
fenA fen is a type of wetland fed by surface and/or groundwater. Fens are characterized by their water chemistry, which is neutral or alkaline...
s and conifer or hardwood swamps.
By some classifications, shrub swamps must have at least 50% shrub cover and less than 20% tree cover. Other definitions specify large shrubs with small trees less than 35 feet in height. Creation of shrub swamps often follows a catastrophic event in a forested swamp (flood, cutting, fire, or windstorm). Another route of development is via drained meadows and fens which progress to shrub swamps as a transitional state to forested swamps.
Development
As a wet meadow matures it begins to fill in with vegetation and as this decomposes the soil thickens creating high spots (
hummockA hummock is a boss or rounded knoll of ice rising above the general level of an ice-field, making sledge travelling in the Arctic and Antarctic region extremely difficult and unpleasant....
s) above the water. Shrubs and small trees begin to grow on these. Shrub swamp water comes from run-off, streams and rivers and the water moves in and out of the swamp throughout the year. Consequently, they tend to be drier than wet meadows or forested swamps and permit water intolerant plant species to grow on the hummocks. Shrub swamps typically occur on organic soils, such as
muckMuck can refer to:*Muck *Muck, Scotland, an island in Scotland*Muck , a number of actions *Muck , sorting out the rich ore from the poor rock in an underground metallic mine after blasting...
and shallow peat soils. Common plants found in the shrub swamps of
North AmericaNorth America is the northern continent of the Americas, situated in the Earth's northern hemisphere and in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific...
include
alderAlder is the common name of a genus of flowering plants belonging to the birch family . The genus comprises about 30 species of monoecious trees and shrubs, few reaching large size, distributed throughout the North Temperate Zone and in the Americas also along the Andes southwards to...
s,
willowWillows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
s, elderberry and highbush blueberry.