Bullers of Buchan Coast
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CITATION MORRONE BIRKWOOD SITE OF SPECIAL SCIENTIFIC INTEREST Aberdeenshire Site code: 1190 NATIONAL GRID REFERENCE : NO135902 OS 1: 50 000 SHEET NO: Landranger 43 1: 25 000 SHEET NO: Explorer 387 AREA: 328.3 hectares NOTIFIED NATURAL FEATURES Geological : Quaternary geology Quaternary of Scotland and geomorphology Biological : Woodlands : Upland birch woodland : Uplands : Juniper scrub : Alpine heath : Rocky slopes : Subalpine calcareous grassland : Spring-head, rill and flush : Subalpine flush : : Basin fen : Vascular plants : Vascular plant assemblage : Non-vascular plants : Bryophyte assemblage : Fungi assemblage : Invertebrates : Invertebrate assemblage DESCRIPTION Morrone (859m) is a foothill of the Cairngorms, overlooking Braemar, on south Deeside. The hill itself is dominated by acid granulites/schists but a band of calcareous schist/limestone on the mid slopes gives rise to small crags and a series of calcareous springs and flushes. The site supports a number of important habitats, and rare animal and plant species. The site has also yielded pollen and plant microfossils that are important for the study of vegetation history and environmental change over the last 12 500 years. GEOLOGY Quaternary of Scotland Morrone is important for Devensian Lateglacial and Holocene palaeoecological studies and palaeoenvironmental reconstruction. Stratigraphic, pollen and plant macrofossil analyses, supported by radiocarbon dating, have provided a palaeoenvironmental record over the last 15 000 years that has helped elucidate the vegetation and climate history of an area that is of outstanding importance today for its arctic-alpine and northern-montane plant communities. The plant macrofossil record for the Lateglacial period is particularly rich, allowing detailed vegetation and Page 1 of 4 A23067.doc environmental reconstructions to be made. Together, the pollen and plant macrofossil records demonstrate the local persistence of elements of a flora that occurred more widely during the Lateglacial. BIOLOGY Habitats The slopes below the band of calcareous outcrops support a mixture of juniper scrub and birch woodland, within which the calcareous springs and flushes form natural glades. Areas of calcareous grassland also occur, particularly adjacent to the limestone crags. Open ground adjacent to the wood is mainly typical sub-montane heather moorland. Boreal and alpine heaths are found on the slopes above the wood and on the summit. Woodland and scrub Morrone Birkwood is regarded as the best example of a sub-alpine birch-juniper wood with herb-rich flora on base-rich soils in Britain. Most of the woodland has a fairly open canopy of the Highland sub-species of downy birch Betula pubescens ssp. odorata over a generally dense shrub-layer of common juniper Juniperus communis ssp communis. The field-layer beneath the juniper is rich in dwarf shrubs and has an unusual variety of herbs including stone bramble Rubus saxatilis, globeflower Trollius europaeus, nodding mellick Melica nutans, the rare intermediate wintergreen Pyrola media, and the rare twinflower Linnaea borealis. In places, particularly on the lower ground, birch is more vigorous and the shrub and field layers are relatively sparse. Locally at Woodhill, bird cherry Prunus padus and hazel Corylus avellana are also found, and the field layer is richer in tall herbs such as dog’s mercury Mercurialis perennis, meadowsweet Filipendula ulmaria and wood cranesbill Geranium sylvaticum. Crags The limestone crags support species such as the rare alpine cinquefoil Potentilla crantzii, serrated wintergreen Orthilia secunda and mountain sorrel Oxyria dignya, along with green spleenwort Asplenium viride and holly fern Polystichum lonchitis, and are also important for bryophytes. These include a number of rare northern mosses such as Stegonia latifolia, Schistidium trichodon, Encalypta rhaptocarpa and Orthothecium rufescens. The rare lichen Gyalecta ulmi is also found. Calcareous grassland The grassland of the limestone outcrops, often occurring in close association with small areas of species-rich heath, widely supports species such as common rock- rose Helianthemum nummularium, northern bedstraw Galium boreale, alpine bistort Persicaria vivipara and alpine cinquefoil. In addition, frog orchid Dactyllorhiza viridis, and the rare spignell Meum athamanticum are also found. Page 2 of 4 A23067.doc Calcareous springs and flushes Calcareous flush and spring communities of moderately high altitudes are well developed, and consist of springs dominated by the moss Palustriella commutata, stony flushes characterised by yellow mountain saxifrage Saxifraga aizoides, and more closed swards of small-sedges in mixture with brown mosses. Arctic-alpines and montane species are well represented, including rare species such as alpine rush Juncus alpinoarticulatus, variegated horsetail Equisetum variegatum and hair sedge Carex capillaris, along with Scottish asphodel Tofieldia pusilla and three- flowered rush Juncus triglumis. These flushes also support a number of rare northern bryophytes including Barbilophozia quadriloba, Sphagnum platyphyllum , Amblyodon dealbatus and Cinclidium stygium. Morrone has some of the best examples of these rare habitats in the United Kingdom. Hollows in the morainic ground near the northern boundary of the site support calcareous sedge mires with bladderwort Utricularia species. Alpine and boreal heath The boreal heath, amongst the heather moorland of the north-facing slopes above the wood, is characterised by sphagnum mosses, cloudberry Rubus chamaemorus and hare’s-tail cottongrass Eriophorum vaginatum. Dwarf cornel Cornus suecica and northern bilberry Vaccinium uliginosum are also found. The alpine heath of the upper slopes and summit of Morrone is dominated by wind- pruned heather with abundant lichens, and shows patterned wave erosion near the summit. The rare lichen Flavocetraria nivalis occurs quite widely here, along with trailing azalea Loiseluria procumbens. Species Flora The flora is unusually diverse, and a total of nearly 1000 plant species are recorded. These include a number of rare species of vascular plant and bryophyte associated with particular habitats (see above). In addition, shady horsetail Equisetum pratense is found in heath above the woodland, and the moss Grimmia incurva is found in scree. The pollen record suggests that the present flora has survived comparatively unchanged since early post-glacial times and it bears a close resemblance to limestone areas in the sub-alpine zone of Norway. Fungi The grassland supports a nationally important assemblage of grassland fungi with seventeen species of waxcap (Hygrocybe), thirty species of pinkgill (Entoloma) and three species of earthtongue (Geoglossaceae) currently recorded. Page 3 of 4 A23067.doc Fauna The invertebrate fauna is an important one, with a high proportion of northern and montane species and a number of national rarities. These include the flies Dorylomorpha beckeri and Spilogona griseola and the moths Kessleria saxifragae and Dichomeris juniperella. Other rare invertebrate species include the beetle Scolytus ratzeburgi, the pearl bordered fritillary butterfly Boloria euphrosyne and Geyer’s whorl snail Vertigo geyeri. NOTIFICATION HISTORY First notified under the 1949 Act: 1972. Re-notified under the 1981 Act: 28 June 1984. Notification reviewed under the 2004 Act: 14 June 2011. REMARKS Measured area of site corrected (from 336.15 ha). Part of Morrone Birkwood SSSI is designated as Morrone Birkwood Special Area of Conservation for the following European habitats and species listed below. Habitats: Dry grasslands and scrublands on chalk or limestone Juniper on heaths or calcareous grasslands Alpine and subalpine heaths High-altitude plant communities associated with areas of water seepage Hard-water springs depositing lime Base-rich fens Species: Geyer’s whorl snail Vertigo geyeri Page 4 of 4 A23067.doc .