Potarch
Also within
Condition (NatureScot)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| F1 | Oligotrophic river/stream | Unfavourable Declining | — | 2019-03-22 |
| F2 | Lowland neutral grassland | Favourable | — | 2009-11-04 |
Habitats
Description
Potarch The Bridge of Potarch crosses the River Dee 12 km upstream of Banchory. The stretch of riverbank either side of the bridge holds the best example of species-rich grassland along the River Dee. Over 150 species of vascular plant have been recorded including Mackay's horsetail Equisetum xtrachyodon, a rare hybrid between rough horsetail Equisetum hyemale and variegated horsetail Equisetum variegatum, which was first discovered here in 1841. Other wild flowers include globeflower Trollius europaeus, spignel Meum athamanticum, imperforate St John’s-wort Hypericum maculatum and melancholy thistle Cirsium heterophyllum. The Potarch section of the River Dee, the best example of a large, nutrient-poor, river in Britain, has diverse in-stream habitat which is unusually rich in bryophytes and lichens including the mosses Hygrohypnum ochraceum and Schistidium rivulare, the lichen Dermatocarpon meiophyllizum and the rare river jelly lichen Collema dichotomum. The endangered freshwater pearl mussel Margaritifera margaritifera is also found.
Species mentioned
Show the 10 species mentioned in the description, with red-list status| English name search for this in other sites |
Latin name search with Google |
IUCN / Red List | Type | Family |
|---|---|---|---|---|
| freshwater pearl mussel | Margaritifera margaritifera | Not listed in GB list | bivalve | margaritiferidae |
| melancholy thistle | Cirsium heterophyllum | LC | herb | asteraceae |
| rough equisetum | Equisetum hyemale | LC | herb | equisetaceae |
| variegated horsetail | Equisetum variegatum | LC | herb | equisetaceae |
| imperforate St. John's-wort | Hypericum maculatum | LC | herb | hypericaceae |
| spignel | Meum athamanticum | LC | herb | apiaceae |
| globe flower | Trollius europaeus | VU | herb | ranunculaceae |
| river jelly-lichen | Collema dichotomum | Not listed in GB list | lichen | no common name |
| claw brook moss | Hygrohypnum ochraceum | Not listed in GB list | moss | hypnales |
| river grimmia | Schistidium rivulare | LC | moss | grimmiales |
Plant communities
A14 — Fast flowing river and stream
Myriophyllum alterniflorum community
Show 15 indicator speciesIsolepis fluitans, Juncus bulbosus, Fontinalis antipyretica, Lobelia dortmanna, Equisetum fluviatile, Myriophyllum alterniflorum, Lemna minor, Callitriche stagnalis, Littorella uniflora, Potamogeton filiformis, Potamogeton gramineus, Potamogeton natans, Ranunculus peltatus, Chara spp., Nitella hyalina
A17 — Chalk river and stream, Fast flowing river and stream
Ranunculus penicillatus ssp. pseudofluitans community
Show 11 indicator speciesBerula erecta, Nasturtium officinale, Elodea canadensis, Lemna minor, Callitriche stagnalis, Veronica beccabunga, Polygonum amphibium, Polygonum hydropiper, Potamogeton crispus, Potamogeton pectinatus, Ranunculus penicillatus ssp. pseudofluitans
A18 — Fast flowing river and stream
Ranunculus fluitans community
Show 12 indicator speciesFontinalis antipyretica, Fontinalis squamosa var. curnowii, Myriophyllum alterniflorum, Myriophyllum spicatum, Elodea canadensis, Mentha aquatica, Lemna gibba, Lemna minor, Potamogeton perfoliatus, Ranunculus fluitans, Glyceria fluitans, Phalaris arundinacea
A9 — Fast flowing river and stream, Marginal and inundation, Pond ditch and canal, Sluggish river and stream
Potamogeton natans community
Show 20 indicator speciesSchoenoplectus lacustris, Juncus bulbosus, Sparganium angustifolium, Sparganium erectum, Sparganium minimum, Alisma plantago-aquatica, Lobelia dortmanna, Equisetum fluviatile, Myriophyllum alterniflorum, Elodea canadensis, Lemna minor, Lemna trisulca, Nymphaea alba, Callitriche platycarpa, Callitriche stagnalis, Littorella uniflora, Potamogeton natans, Ranunculus trichophyllus, Glyceria fluitans, Chara subspinosa
Insects to look out for
These moths and butterflies 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.
| Species | Status | Via host-plant |
|---|---|---|
| Golden plusia Polychrysia moneta |
Endangered | Trollius europaeus |
| Satyr pug Eupithecia satyrata |
Vulnerable | Hypericum spp. |
Hostplant 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 (Open Government Licence). Contains data supplied by UK Centre for Ecology & Hydrology.