Caithness Field club Bulletin
April 1975

HUNTING FOR CAITHNESS MOSSES AND LIVERWORTS
K. Butler

Mosses and liverworts are small plants which are grouped together under the name Bryophytes. They are not easy to study, mainly because most of them are minute and have to be identified by examination under a microscope. In spite of this a devoted 'bryologist' can learn to recognise a considerable number of species in the field, and such a person is probably a member of the British Bryological Society.

The mosses of Caithness were studied by the Rev. David Lillie when he was minister at Watten in the early years of the century. He became nationally prominent in the field of bryology and his finds in Caithness were sometimes important ones. Since his time little had been done to study Caithness bryophytes until the public enquiry about Dunnet Bay stimulated some interest in the fine moss flora of that area. In 1974 the Bryological Society chose to hold a one-week meeting in the county to see what it could offer. Most of them came expecting that it would be a dull county because the most interesting bryophytes tend to grow on limestone rocks and there are none of that type. However the dune links and some of the sandstone rocks are rich in calcium and these areas proved to be most interesting.

The passage of the moss-hunters did not go un-noticed. They had the undignified habit of doing a 'bottoms-up' with knees and nose to the ground in the middle of roads, harbours, barley fields and the golf-course, to the evident amazement of the local populace. The results are impressive - adding 27 new species to the county list and a great deal of detail to the knowledge of the area.

The meeting was reported in the BBS Bulletin (no 25, Jan 1975) and is reproduced below by kind permission of the Society

THE SUMMER MEETING, 1974
CAITHNESS

* New vice-county record throughout

The first week of the meeting was based on Thurso from 25 - 30 August. The aim was to cover ground in the most north-eastern part of Britain, little known to past British bryologists with the notable exception of Rev. David Lillie of Watten. The possibility of refinding some of the rarities recorded by him some seventy years ago added considerable interest to the meeting. About twelve members attended for most of the week; excursions were restricted to the northern and eastern parts of Caithness (v. -c. 109) except for one made by a member to W. Sutherland (v. -c. 108).

25 August. The day was spent on the dunes of Ackergill and Keiss Links fringing Sinclair's Bay. On the main dune ridge of Ackergill Links Hypnum cupresiforme var. tectorum* and Entodon concinnus were seen, also Bryum bicolor agg*. on a wooden footbridge. Fixed dunes on the landward side produced Bryum inclinatum and Amblyodon dealbatus. Keiss Links, after we had forded the Burn of Lyth, proved more interesting, the first find being Bryam marratii* on damp sand by a backwater. Hollows on the fixed dunes nearby contained Scapania aspera, Distichium inclinatum, Encalypta rhabdocarpa, Pottia heimii, Tortella fragilis in quantity, Catoscopium nigritum and Drepanocladus vernicosus. One member concentrated on the ubiquitous oatfields of the county. One such habit at Skirza, near Freswick Bay contained Ditrichum cylindricum, Dicranella staphylina Bryum sauteri*, B. violaceum and B. rubens.

26 August. The first coastal ravine visited was that of the Dunbeath Water. Boulders in the stream bed a short distance above Dunbeath supported Solenostoma cordifolium*, Scapania subalpina and Barbula spadicea. A small stubble field nearby contained Anthoceros husnotti and Ephemerum serratum var. minutissimum*. Further upstream the valley became more wooded with considerable sandstone exposure. Shady rock faces supported Lejeunea cavifolia* and Bartramia pomiforis var.elongata*, while on the wooded slopes Fossombronia pusilla and Pohila lutecens* were noted on soil, Scapania nemorea* on a boulder and 0rthotrichum pulchellum on hazel. By the river detritus-filled rock crevices yielded Plectoclea paroica*. Further work was curtailed by heavy rain but one member continued to search oatfields. In one at Buoltach near Latheron, Ditrichum pusillum*, Pseudophemerum nitidum and Pohlia pulchella* were collected; another at Spital near Halkirk produced Dicranella staphylina and Bryum sauteri.

27 August. The morning excursion explored the partly wooded valley of the Strath Burn near Watten, from Strath southwards to Scorriclet. On a grassy riverside bank near Strath Weissia microstoma var. brachycarpa* was detected, considerably extending its known Brit. range. On wooded slopes in the area Plagiothecium laetum* occurred on soil, and Pohlia rothii* mixed with P. annotina on a gravelly path. Towards Scorriclet basic flushes were conspicuous and contained Pellia neesiana*, Trichocolea tomentella, M?nium rugicum*, Acrocladium stramineum and A. giganteum. A search in a barley field near Strath revealed Bryum sauteri, B. Klinggraeffii and B. violaceum. After lunch the party proceeded via Kensary to the Dubh Lochs of Shielton and extensive sphagnum-dominated system of treacherous pools on very acid blanket bog. Numerous Sphagna were seen including fine hummocks of S. imbricatum and S. fuscum. Associated species were Pleurozia purpurea, Campylopus brevipilus and gemmiferous Aulacomnium palustre. Tortula ruraliformis was noted on an outbuilding roof at Rowens.

28 August. The Links of Dunnet Bay, a locality well-known to Lillie, were chosen for the main excursion. A young conifer plantation provided shelter from the cold wind and its ditches and damp sandy hollows supported a rich bryophyte flora associated with Primula scotica; Tortella fragilis and T. inclinata were in abundance with Leiocolea bantriensis, Encalypta rhabdocarpa, Barbula revoluta, Catoscopium nigritum, Philonotis calcarea and Drepanocladus vernicosus. Beyond the wood exposed damp hollows contained fruiting Meesia uliginosa and Amblyodon dealbatus. Later in the day other localities yielded Bryum neodamense in quantity on damp Gravel by the Loch of Mey, Nowellia curvifolia* on fallen trees in woodland at Castletown and Campylopus brevipilus and Bryum intermedium on spoil heaps in an adjacent 'flagstone' quarry.

One member ventured into the coastal part of West Sutherland (v. -c. 108) for the day, examining oatfields. In the best of these, at Calgarry Beg near Melvich, Ditrichum cylindricum, D. pusillum*, Pohlia pulchella*, Bryum tenuisetum* and B. Rubens were found.

29 August. The sandstone gorge on the River Thurso at Dirlot was the venue for the morning. Here Lillie added Barbilophozia atlantica to the British Flora in 1901, and it was refound growing on dry rocks with Cynodontium bruntonii and Orthotrichum rupestre. Species found in the gorge itself were Cololejeunea calcarea and Seligeria Recurvata on damp rock faces, Sphagnum teres in a flush and Polytrichum nanum on damp soil. Dicranella crispa* c.fr. occurred above the gorge on a sandy footpath. The fine weather prompted an afternoon visit to the north coast at Crosskirk Bay. A small oatfield there contained Dicranella staphylina, Bryum ruderale and B. violaceum, confirming the widespread occurrence of these species in the area. Careful searching of damp cliff-top soil nearby was rewarded with Archidium alternifolium, Tortella flavovirens var. flavovirens, Amblystegium serpens var. salinum, Bryum micro-eruthrocarpum, Ephemerum serratum var. serratum* and Lejeunea patens* (the last in a damp grassy hollow).

30 August. Hilly ground below Warehouse Hill near Ulbster was chosen for the morning of the final day, and despite thick mist a good number of interesting species were seen. Patches of marshy ground produced Calypogeia neesiana var. neesiana*, Chiloscyphus pallescens*, Cephalozia leucantha and Sphagnum contortum. On mud by a partially drained loch below Warehouse Hill species of interest were Fissidens osmundoides*and Acrocladium sarmentosum. By Groat's loch nearby were Fossombronia foveolata* and Haplomitrium hookeri* both with mature sporophytes. An interesting find between the two lochs was Tayloria longicolla freely fruiting on damp peaty patches amongst heather. This species was known to Lillie from three other Caithness localities, but had not been seen in Britain for many years. Another oatfield search at Smerlie near Lybster produced Bryum riparium*. Weissia rutilans grew on a rock on moorland near Whaligoe Ulbster. After lunch the final excursion was a rather brief visit to the lower part of the Reisgil Burn at Lybster, a deep ravine cut through base-rich sandstone. Solenostoma pumilum and Hygroamblystegium fluviatile grew on boulders in the stream, while on the damp ledges above grew Blepharastoma trichophyllum, Scapania cuspiduligera*, Radula lindbergiana, Cololejeunea calcarea, Distichium capillaceum, Gymnostomum recurvirostrum, Eucladium verticillatum, Campylium protensum* and Rhynchostegiella pumila*.

During a very enjoyable and interesting week mapping cards were compiled for twelve grid squares and a good number of rare species seen. Much credit must go to Mr. J. K. Butler whose expert local knowledge and efficient organisation proved invaluable. Results of the week suggest that further work in the county, particularly in the remote western areas, on the high ground and in other coastal ravines, would be well worthwhile.

David G. Long.