Shrub swamp
Encyclopedia
Shrub swamps, also called scrub swamps or buttonbush swamps, are a type of freshwater
wetland
ecosystem
occurring in areas too wet to become hardwood swamp
s (“true” or forested swamps), but too dry or too shallow to become marsh
es. They are often considered transitional (“mid-successional”) between wet meadow
s or fen
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.
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 muck
and shallow peat soils. Common plants found in the shrub swamps of North America
include alder
s, willow
s, elderberry
and highbush blueberry.
http://www.maine.gov/dep/blwq/wetlands/shrub.htm
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
occurring in areas too wet to become hardwood swamp
Swamp
A swamp is a wetland with some flooding of large areas of land by shallow bodies of water. A swamp generally has a large number of hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodical inundation. The two main types of swamp are "true" or swamp...
s (“true” or forested swamps), but too dry or too shallow to become marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....
es. They are often considered transitional (“mid-successional”) between wet meadow
Wet meadow
A 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 fen
Fen
A fen is a type of wetland fed by mineral-rich surface water or groundwater. Fens are characterised by their water chemistry, which is neutral or alkaline, with relatively high dissolved mineral levels but few other plant nutrients...
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 (hummockHummock
A 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 muck
Muck
Muck can refer to:*Muck *Muck, Scotland, an island in Scotland*Isle of Muck, a small island connected by sand spit to Portmuck, County Antrim, Northern Ireland*Muck , a number of actions...
and shallow peat soils. Common plants found in the shrub swamps of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
include alder
Alder
Alder 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 along the Andes southwards to...
s, willow
Willow
Willows, 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
Elderberry
Sambucus is a genus of between 5 and 30 species of shrubs or small trees in the moschatel family, Adoxaceae. It was formerly placed in the honeysuckle family, Caprifoliaceae, but was reclassified due to genetic evidence...
and highbush blueberry.
Notable shrub swamps
- Canaan ValleyCanaan ValleyCanaan Valley is an oval, bowl-like upland valley in northeastern Tucker County, West Virginia, USA. Within it are extensive wetlands and the headwaters of the Blackwater River which spills out of the valley at Blackwater Falls...
, West Virginia - Cranberry Glades, West Virginia
http://www.maine.gov/dep/blwq/wetlands/shrub.htm