|Scientific name||Betula pubescens – Rubus fruticosus woodland|
|Common name||Downy Birch – Bramble woodland|
Download full pdf synopsis: WL4D
This is a rather variable birch woodland assemblage, lacking the distinctive character of the other communities within group WL4. Betula pubescens is typically the main component of the medium-height canopy, while Salix cinerea is also a constant but characteristically sub-ordinate to birch. Fraxinus excelsior is frequent but not abundant. Sorbus aucuparia, Quercus robur, Alnus glutinosa, Fagus sylvatica and Acer pseudoplatanus all occasionally occur in the canopy, whilst beneath, Ilex aquifolium and Crataegus monogyna are frequent in the understorey. The field layer is usually a somewhat uninspiring mixture of Rubus fruticosus agg., Hedera helix and Dryopteris dilatata. On depauperate peaty soils Rubus idaeus occasionally occurs, whilst Viola riviniana/reichenbachiana, Dryopteris affinis and Geranium robertianum may be encountered where the substrate is more base-rich. Thuidium tamariscinum, Kindbergia praelonga, Eurhynchium striatum and Hypnum cupressiforme usually form the majority of the bryophyte layer.
This community mostly occurs on basin peats but may also be found on well-drained mineral soils, gleys or podzols. It is usually found on flat ground in the lowlands, but can occur on gentle slopes. Soil conditions are more base-rich and more fertile than typical for birch stands, and some periodic inundation may occur on sites near rivers or lakes. Whilst this community, like Irish birch woodlands in general, is commonly associated with degraded raised bogs, included here are also seral stages on more mineral soils which may succeed to the mature woodlands of other groups.
No sub-communities have been described for this community.
From most communities in the other woodland groups, this community will be differentiated by the greater birch component within the vegetation. From the other communities within group WL4, the presence of species indicative of mineral soil provides a guide.
This is not a particularly species-rich woodland community but it has a reasonably diverse bryophyte flora. A small proportion of stands qualify as EU Annex I habitat 91E0 Residual alluvial forests*. These occur along rivers and lakes and are subject to periodic inundation.
The main threats to these woodlands include overgrazing by deer or livestock, woodland clearance and invasion by non-native species such as Rhododendron ponticum, Acer pseudoplatanus and Fagus sylvatica. Undergrazing may also occur, however, resulting in dense thickets of bramble that reduce field layer diversity.