|Scientific name||Fraxinus excelsior – Galium palustre woodland|
|Common name||Ash – Marsh Bedstraw woodland|
Download full pdf synopsis: WL3A
This highly diverse wet woodland community has a medium-height canopy largely composed of Fraxinus excelsior and Alnus glutinosa with some Salix cinerea and Betula pubescens. Ilex aquifolium is usually found in the understorey while Corylus avellana and Crataegus monogyna are also frequent. The field layer has a large number of constant species including wetland indicators (Filipendula ulmaria, Carex remota, Galium palustre and Ranunculus repens) alongside species of drier but moist substrates (Hedera helix, Rubus fruticosus agg., Lonicera periclymenum, Dryopteris dilatata, Athyrium filix-femina, Oxalis acetosella, Viola riviniana/reichenbachiana, Geranium robertianum and Circaea lutetiana). The bryophyte layer is mainly composed of a standard woodland assemblage of Thuidium tamariscinum, Plagiomnium undulatum, Kindbergia praelonga, Eurhynchium striatum, Isothecium myosuroides and Hypnum cupressiforme, but species that are common on damper soils, such as Pellia epiphylla, Hookeria lucens and Calliergonella cuspidata, are also frequent.
These stands most often occur on base-rich, gleyed soils, but sometimes on basin peats or the damper types of well-drained mineral soils and usually have a fairly low organic component. They are found chiefly in the lowlands on flat ground, in hollows, near rivers, along lakeshores, or on the flushed slopes of hillsides. Soils, which may be waterlogged but are not usually subject to inundation, are of medium fertility in relation to other woodlands.
No sub-communities have been described for this community.
These stands are close to those of community WL3C in which Alnus and Fraxinus are also constants. The present community, however, is more species-rich with a greater component of Salix cinerea and Betula pubescens while Acer pseudoplatanus is seldom encountered.
This is on average an exceptionally species-rich woodland community with a diverse bryophyte flora. Stands along rivers and lakes which are subject to periodic inundation qualify as EU Annex I habitat 91E0 Residual alluvial forests*.
The main threats to these woodlands include changes to hydrological regimes, overgrazing by livestock (usually cattle), woodland clearance and invasion by non-native species.