On the wildside: Secrets of the bryophyte world

Having spent a good number of years being fascinated with the wild flowering plants of Britain I have only superficially looked at another large group of plants, the bryophytes – mosses and liverworts.

I decided that if I am to become anything like competent at identifying these wonderful little plants, more effort was required, so I have been taking advantage of the great expertise of a small group of moss and liverwort specialists (bryologists) from The Royal Botanic Garden Edinburgh, led by Dr David Long, who record the distribution of bryophytes in the Borders.

A recent excursion to the Talla valley in the Tweedsmuir hills proved most rewarding.

Even though the weather was not the best, being damp and drizzly as we walked up the valley, the vegetation was beginning to exhibit the first hints of autumn with the Deer Grass turning to orange-brown and some of the Cotton Grass beginning to redden. These seasonal changes in a way mirror those of the plumage of birds or coats of some mammals. A few late-flowering clumps of Wild Thyme and, higher in the tumbling burns, some Water Forget-me-nots provided additional highlights of colour.

However, we were there to record bryophytes and during the day over 70 species were listed as we traversed the varied terrain and habitats including boggy mire, wet grassland, sheltered ledges and open screes.

In the same way as the occurrence of particular flowering plants indicate certain environmental conditions, this is also true of bryophytes.

Learning these ‘environmental indicators’ amongst the mosses and liverworts is particularly fascinating as they often provide further evidence to that of flowering plants.

In addition, the range of form, colour and habit of these remarkable plants is seemingly infinite.

To re-find and recognise a newly learnt moss in the field, no matter how common, somehow provides greater satisfaction than the exotic and dramatic images we are now used to seeing in televised natural history programmes.

One of the highlights of the excursion was the reddish patches of Duval’s Thread-moss (Bryum weigelii) on high, spongy open ground. We were alerted that we might find this moss, so having familiarised myself with its characteristic features from the literature, it was exciting to see the plant in its natural habitat and also to discover how discernible its characters were.

A rewarding part of learning to study any new group of organisms, is gaining an appreciation of the level of subtlety of features that separate and identify species. The best way to progress is to get out in the field with experts! I shall look forward to more bryophyte excursions with the Borders specialists and feel privileged to join them.