Greenlaw’s Dogden Moss proves a real wetland gem

Large Heath Dogden Moss
Large Heath Dogden Moss

Dogden Moss is an extensive flat wetland area, over a mile wide, just north-west of Greenlaw, technically classed as a ‘raised mire’.

It is the best of its kind in the Borders, and designated as a ‘Site of Special Scientific Interest’. It consists mostly of deep, spongy wet peat with tussocky clumps of heather and lots of colourful Bog Moss (Sphagnum) of which twelve different kinds have been found here.

During the First World War, Sphagnum moss was harvested in bulk in southern Scotland, dried and sent to France as a highly effective wound dressing for injured soldiers, due to its excellent absorbent and antiseptic properties. The bog is an ancient relic landscape surviving from the last ice age, when the retreating ice left behind the internationally-famous Bedshiel Kaims, long snaking moraine ridges (technically eskers) visible from satellites and from the Westruther road.

These sand and gravel ridges trapped water leading to the development of the bog over several thousand years. The Kaims are considered to be the best example of eskers in southern Scotland. Past attempts to drain the bog can be seen in the traces of old ditches. Fortunately these attempts failed and the bog remains in good condition.

An old record for a rare but beautiful insect, the Large Heath Butterfly, prompted a small group of us to visit the bog on a fine summer’s day last July, when, after hours of tiring trudging across the hummocks and hollows, we counted more than 30 of these splendid insects on the wing, along with two large day-flying moths, the Northen Eggar and the Wood Tiger.

These insects were all brought out by the warm weather, which also made it ideal for the resident Adders to sunbathe, and two of these were seen and carefully avoided. Red Grouse were abundant as well as several Curlew and a Snipe.

Apart from its rare Sphagnum mosses, Dogden Moss has several other locally special plants including the creeping Cranberry, whose tasty fruits are much smaller than the imported commercial variety, and another very rare moss, the Waved Fork-moss, which has only four other Scottish sites. This is a hard plant to find, and hours of walking revealed only 11 small clumps identified by their wavy leaves. A very special and striking plant, quite abundant here growing in the Sphagnum moss, and conspicuous by its bright red leaves and tiny white flowers was the Round-leaved Sundew.

The reward for our efforts was the welcome conclusion that the Large Heath Butterfly still flourishes in Berwickshire in this beautiful and colourful wetland. Dogden Moss may still have more secrets to be revealed in the future.

Tonight (Thursday) Ron McBeath and Stan Da Prato are giving us a slideshow on ‘Travels in Tibet’. We meet at 7.30pm in the Duns Parish Church Hall, entry is £1.50.