Craig Royston Woods

Also within

Stirling and Falkirk County LochLomond National Park National Park Loch Lomond Scenic Area

Condition (NatureScot)

Habitats

Coppiced woodland, Fast flowing river and stream

Birds & fish recorded

Birds

Description

CRAIG ROYSTON WOODS The Craig Royston Woods Site of Special Scientific Interest (SSSI) is located along the north-east side of Loch Lomond on steep west facing slopes south of Inversnaid. Craig Royston Woods are part of the extensive oak woodlands found throughout Loch Lomondside. The diversity of the understory vegetation and the age of the woodlands support a wide variety of moths. Craig Royston Woods are made up of ancient natural woodland with mostly sessile oak Quercus petraea as well as long established woodland plantations derived from non-locally sourced pedunculate oaks, Quercus robur and their hybrid. The oaks often have a multi-stemmed structure suggesting that they were coppiced at some point. The removal of the wood from the managed coppice created an open glade environment with relatively little understory shrub growth and a high continuous canopy. Areas of mixed canopy comprised of birch Betula pubescens, alder Alnus glutinosa, ash Fraxinus excelsior, hawthorn Crataegus monogyna and wych elm Ulmus glabra occur on the flushed shoreline, stream sides, inaccessible crags and localized areas of nutrient-rich soil. hazel Corylus avellana is common in open areas. The steep terrain with many rock outcrops and wooded ravines supports species-rich bryophyte and flowering plant communities that are characteristic of western sessile oak woods. The occurrence of the nationally-uncommon Tunbridge filmy fern Hymenophyllum tunbrigense, Wilson’s filmy fern H. wilsonii and Hageniella micans, which is a nationally very restricted moss, indicates the “Atlantic” nature of these woods. Localised outcrops of nutrient-rich rocks support species such as the green spleenwort Asplenium viride and the purple saxifrage Saxifraga oppositifolia that are characteristic of this habitat and very sparsely distributed within the area. The site is notified for its moths because it has the Red Book Data species vulnerable moth Acleris abietana, five nationally-scarce species, Atemelia torquatella, Eupithecia plumbeolata, Olethreutes arcuella, Pammene albuginana, Scoparia ancipitella and a long list of more common species. Other fauna includes the largest breeding populations of pied flycatcher Ficedula hypoleuca within the Loch Lomond deciduous woodland. The woods support characteristic invertebrate populations including several colonies of the wood ant Formica aquilonia and a number of notable beetles.

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