Includes bog, marsh, and fen.
Fens typically have groundwater sustaining them as wetlands, with vegetation, often (but not exclusively) growing over peat, where the water-table is at, or just below, the surface. Water is derived from both rainfall and drainage of surrounding land. Some fens may have Sphagnum moss, but typically the vegetation is dominated by tall reeds, wetland herbs, sedges, and rushes.
Bogs have vegetation growing on wet peat; the water source is direct rainfall, or in some cases, over-land flow during heavy rain events. Sphagnum moss is always present, often with bog cotton (Eriophorum). In locally drier areas heather (Calluna, Erica) may also be present, but never dominant
If you'd like to provide a correction or improvement to the definition given above, please contact the wiki administrators via the contacts page.
Marsh habitat includes tall grasses and rushes on periodically wet ground (unlike fen or bog that are permanently wet), or where wetland herbs are an important component of the ground flora (e.g. meadowsweet – Filipendula ulmaria, marsh orchids – Dactylorhiza spp., kingcup – Caltha palustris, valerians – Valeriana spp.).
A Flush is a collective term for wet areas near springs where water emerges from the ground or seeps from fissures in rock faces, or valley slopes. Flushes are fed by groundwater – when surface water predominates a stream is formed.