Report Cover Vol I - Clare County Library

The County Clare Wetlands Survey Patrick Crushell & Peter Foss 2008
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extent may be difficult to determine before mid-May. Unlike tall-herb swamps - FS2 below, the
broadleaved herb component is minor. Vegetation typically lacks stratification as there is little or no
development of an understorey element. In some situations there may be a mixture of other species such
as Common Marsh-bedstraw (Galium palustre), Water Mint (Mentha aquatica), forget-me-nots (Myosotis
spp.), Bogbean (Menyanthes trifoliata), Marsh Cinquefoil (Potentilla palustris), Wild Angelica (Angelica
sylvestris), Meadowsweet (Filipendula ulmaria) or Fool's Water-cress (Apium nodiflorum).
FS2 Tall-herb swamps
Tall-herb swamps are comparatively species-rich stands of herbaceous vegetation that occur in wet areas
where the water table is above the ground surface for most of the year, or where water levels fluctuate
regularly as in the case of tidal sections of rivers. Tall or robust broadleaved herbs dominate and common
components include Lesser Water-parsnip (Berula erecta), Fool's Water-cress (Apium nodiflorum),
Gipsywort (Lycopus europaeus), Brooklime (Veronica beccabunga), Hemlock Water-dropwort (Oenanthe
crocata), Hemp-agrimony (Eupatorium cannabinum) and Water Forget-me-not (Myosotis scorpioides).
These swamps may also support Yellow Iris (Iris pseudacorus), Water-plantain (Alisma plantagoaquatica)
and Water Horsetail (Equisetum fluviatile), in addition to occasional reeds, large grasses
(Glyceria maxima, Festuca arundinacea) and sedges. Cover of the latter should, at most, be patchy or
dispersed; swamps that are dominated by reeds, and other large grasses or sedges should be considered
under reed and large sedge swamps - FS1 above. Tall-herb swamps may have an understorey element
with a range of smaller wetland plants.
Links with Annex I: Tall-herb swamps can include pockets of the annexed habitat 'hydrophilous tall herb
fringe communities of plains and of the montane to alpine levels (6430)'. In Ireland, however, stands of
the latter are usually fragmented and poorly developed.
G Grassland and Marsh
This section includes habitats where the vegetation is either dominated by grasses, or is 'grassy' in
appearance with abundant small sedges or rushes. Freshwater marshes are also considered here since
they are difficult to distinguish, on floristic grounds, from some types of grassland.
There are few, if any, natural grasslands in Ireland, particularly in the lowlands, as most have been
modified or managed to some degree by grazing, mowing, fertiliser application or drainage. In the
absence of such management, most grasslands would revert to scrub, woodland or heath. The key
distinction being made in this classification is between grasslands that are improved, defined here as
species-poor and intensively managed grasslands, and those that are unimproved or semi-improved.
Improved grassland is by far the most widespread type and makes up a large proportion of Ireland's
productive farmland. Much of it is reseeded, fertilised or heavily grazed with the result that species
diversity is low. It is of comparatively little conservation interest. Grass leys that are planted as part of an
arable rotation are included in this section, as are areas of amenity grassland that are improved and
managed specifically for recreation, amenity or sport, as opposed to agriculture. 'Semi-natural'
grasslands may receive some inputs of fertiliser (organic or artificial), but they are not intensively
managed and have not recently been reseeded. Low levels of improvement and high levels of grazing can
influence sward composition, reduce species diversity and lead to increased representation of
'agricultural' herbs. These are listed below in the improved agricultural grassland - GA1 category.
Coastal grasslands, other than those of salt marshes (CM1-2) and sand dune systems (CD1-6), are
included in this section. Grassland vegetation should be primarily herbaceous. If cover of dwarf shrubs
exceeds 25%, the habitat should be considered under heath. If scattered trees are prominent in areas of
grassland but canopy cover is less than 30%, the habitat should be recorded as scattered trees and
parkland - WD5.
GS Semi-natural Grassland
GS4 Wet grassland
This type of grassland can be found on flat or sloping ground in upland and lowland areas. It occurs on
wet or waterlogged mineral or organic soils that are poorly-drained or, in some cases, subjected to
seasonal or periodic flooding. On sloping ground, wet grassland is mainly confined to clay-rich gleys and
loams, or organic soils that are wet but not waterlogged. This category includes areas of poorly-drained
farmland that have not recently been improved, seasonally-flooded alluvial grasslands such as the River
Shannon callows, and wet grasslands of turlough basins (See also turloughs - FL6).
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