Acidic Swamp

Description

These are softwood dominated boreal forests most often comprised of mature black spruce (Picea mariana) found on shallow organic over mineral soils. The canopy is often a pure stand of black spruce that is often closed to broken. Other trees that are found in the canopy include balsam fir (Abies balsamea) or tamarack (Larinx laricina). Tall shrubs are generally absent, low shrubs and forbs are often sparse to locally abundant (greater than 30 percent cover). Bryophytes are the dominant groundcover, covering both hummocks and hollows. Natural disturbances by wind create tip-ups of individual trees or small groups of trees that are attributed to the hummock and hollows microtopography. Changes in light availability and soil wetness are the dominant drivers for these communities, with logging being the main factor attributable to large scale changes.

Submodel

Description

These are graminoid and shrub dominated wetlands that are typical successional communities after an alteration to the surrounding landscape increases the local hydroperiods. This is most often the result of beaver damming but can be the result of anthropogenic influences such as building of roads and man-made dams as well. This state may persist indefinitely or may be seen as a transitional community and will depend on the surrounding hydrologic regime. It can be identified by the presence of the sandy or coarse-loamy textures underneath mucky organic soils, compared to other sites which may have deeper organic soils or a root restrictive layer. Standing dead snags may or may not be present depending on time since hydrological change.

Submodel

Description

This state represents a once forested area now cleared for pasture. This will typically only occur on gentler slopes (<15 percent) due to potential for water erosion. Pasture vegetation can consist of grasses, legumes, other forbs, shrubs or a mixture. Many of these forages are introduced, having originally come from areas in other states or continents. Overgrazed pastures can lead to soil compaction and numerous bare spots, which may then become focal points of accelerated erosion and colonization sites of undesirable plants or weeds. In these systems, water control structures may be used to prevent excess water in the fields and historical drainage and cultivation of this site may lead to the loss of the mucky organic surface texture.

Submodel

Description

These are wetlands of emergent vegetation and areas of open water, often reflecting slightly higher seasonal high-water tables or increased long-term hydroperiods. Hydrologic regimes are often the longest in this state, with long-term or permanent inundation influencing the development of freshwater emergent species. Organic soils are often deepest in these states but may often include shallow organics or high organic content mineral soils. These communities will often form near monocultures and be so dense that germination of other species is limited.

Submodel