Tall-sedge bed

Communities generally dominated by tall sedges typically of the order Magnocaricetalia. Cladium mariscus communities are only partly included here. When they develop in calcareous fens they are part of the habitat type D4.1c. The optimal belt for tall sedge vegetation is the geolittoral zone, the area above the mean water level, but subjected to periodical flooding and water saturated for most of the year. Tall sedge communities are usually species-poor, often dominated by one species and accompanied by few characteristic species. Some of the above mentioned dominant species have clear preferences related to climate, substrate, hydrology and trophic level of the habitat.  The primary productivity of these communities is high, but clearly lower than for non-sedges tall helophytes included in the habitat C5.1a.

Tall sedge communities occur also along running waters or in wet and moist depressions of alluvial and karst plains. In the hydro-series they are later replaced by drier wet meadows and riparian shrub vegetation. They grow as fringe vegetation along lakes and ponds, often in mixture with tall reedy helophytes and forbs (habitat C5.1a). In low-productive lakes, particularly in northern Europe, Carex rostrata, C. lasiocarpa and C. aquatilis, with Equisetum fluviatile, are substituting taller reeds in water fringe helophyte vegetation. Such stands are very species poor, sometimes monospecific. However stands dominated by Carex rostrata and C. lasiocarpa in calcareous fens and bogs belong to the habitats D4.1c

Many tall sedges have an effective clonal growth: some species grow in large tussocks raising some tens of centimetres above the substrate. Wet hollows between tussocks, with accumulation of plant remains, are often occupied by small aquatic and emergent herbs and grasses (e.g. Galium palustris s.l., Lycopus europaeus, Ranunculus trichophyllus, Scutellaria galericulata, Lemna spp., Utricularia ssp.), aquatic mosses and hepatics (Calliergon spp., Drepanocladus aduncus, Riccia spp., Ricciocarpos natans). Various mixtures of herbs and grasses often indicate unstable successive states after disturbances.

Tall sedge communities have been earlier used for cattle grazing and mowing, and many have been converted to arable land and pasture. They are largely impacted by water level regulation, construction activities and eutrophication. In recent past eutrophication and decline of grazing has often led to the increase of tall reeds in the lower part of tall sedge communities, and to increase of shrubs and trees in the upper part. Tall plants from drier positions can also invade sedge-dominated stands. In dynamic alluvial landscapes this habitat may exist more sustainable, occupying slightly different sites over different years. In other sites it can only be maintained for longer times by mowing.

Indicators of good quality:

• Natural water and flooding regime
• No alteration of substrate chemistry
• Species poor stands dominated by sedges
• Low cover of annuals, ruderal and/or nitrophilous species
• Low anthropogenic impacts in terms of construction activities, eutrophication, drainage etc.
• No enhanced biomass due to eutrophication or replacement by tall reedy vegetation
• Absence of invasive alien species (e.g. Impatiens glandulifera, Bidens frondosa, Ludwigia spp., Fallopia spp., etc.)
• Shrubs and trees occur in low cover and do not show increasing trends
• Low cover of tall herbs from drier positions and other habitats (e.g. Calystegia sepium, Eupatorium cannabinum, Valeriana officinalis, Cirsium spp., etc.)

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats