Coed Cors y Gedol

Also within

Gwynedd County Eryri / Snowdonia National Park

Habitats

Bracken scrub, Fast flowing river and stream

Geology & landscape

Landscape processes: Glacial

Birds & fish recorded

Birds

Description

Description A biological site Coed Gors y Gedol is selected as one of the best examples of a woodland type for which West Wales is an important centre of distribution. The wood lies on even ground composed of glacial drift which slopes towards the Afon Ysgethin. The bulk of the central area of woodland is composed of young, regenerating sessile oak Quercus Petraea and birch Betula pubescens with smaller amounts of ash Fraxinus excelsior and sallow Salix cinerea. The structural diversity is enhanced by the presence of large amounts of hazel Corylus avellana and or mature woodland to the north and south of the central area. Beech Fagus sylvatica is frequent as older trees with sycamore Acer pseudoplatanus and rowan Sorbus aucuparia. The ground flora is moderately sparse in parts with bramble Rubus fruticosus agg., bluebell Hyacinthoides non-scripta and bracken Pteridium aquilinum being common throughout. A large variety of flowering plants can be found. Grasses such as sweet vernal grass Anthoxanthum odoratum, common bent Agrostis capillaris and the less common wood millet Milium Effusum occur. Other species of interest include globeflower Trollius europaeus, great horsetail Equisetum telmateia, waterblinks Montia fontana and tutsan Hypericum androsaemum. The riverside has rich fern and bryophyte flora. The presence of hay scented fern Dryopteris Aemula is unusual as it is one of a very few sites in North Wales for this species. Rare bryophytes include Porella Pinnata, Philonotis Rigida and Grimmia Retracta. Species of bird include nuthatch, treecreeper, great spotted woodpecker, buzzard and, along the river, dippers. Remarks: Within the Snowdonia National Park.

Species mentioned

Insects to look out for

These moths, butterflies and beetles are known to feed on plants recorded at this site, and carry a notable UK conservation status — but a host-plant being present doesn't mean the insect has actually been recorded here. Treat this as "worth watching for," not a confirmed sighting.

Host-plant data: Cook et al. (2025), Traits data for the butterflies and macro-moths of Great Britain and Ireland, 2024, UK Centre for Ecology & Hydrology / Butterfly Conservation; and Padovani et al. (2020), Database of Insects and their Food Plants (DBIF), UK Centre for Ecology & Hydrology (both Open Government Licence). Contains data supplied by UK Centre for Ecology & Hydrology.

Plant communities