Collins New Naturalist Library. David Cabot

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СКАЧАТЬ 70 m to 400 m. The dry heath community was not described in detail and had to wait for its first precise description by Clark in 1968.¹⁴ Where the heath had been burnt about four years previously, Clark found that western gorse formed a mat of vegetation 20–30 cm tall. In areas untouched by fire for more than ten years the gorse was taller – 30–50 cm – and often more open, leaving room for bell heather, heather and a sparse herb layer of mainly sheep’s fescue and some common bent.

      Western gorse, abundant in eastern Ireland and more local in the west, is characteristically found in coastal, lowland and sub-montane habitats, especially in the Wicklow Mountains where it occurs typically in the upper hill pasture areas before the vegetation changes to heather moorland at about 400 m. The somewhat similar but much taller gorse (also known as furze or whin) occurs typically at lower altitudes in the Wicklow hills and elsewhere in Ireland.

      Higher up in the heather moorland Pethybridge & Praeger described areas, especially on the flat summits, dominated by deergrass and common cotton-grass. On the flat summit of Lugnaquillia Mountain they found a thin skin of vegetation, dominated by the woolly fringe-moss, bilberry, heath bedstraw, heath rush, stiff sedge, the moss Polytrichum commune and colonies of the alpine clubmoss.

      The Wicklow uplands are a disappointment for mountain plants when compared with some of the highland sites in the northern and western counties. Both the arctic-alpine roseroot and the mossy saxifrage, first reported in 1897 and 1927 respectively, have not been found recently and are feared to be extinct.¹⁵ St Patrick’s cabbage and fir clubmoss are found on the mountain itself. The occurrence of St Patrick’s cabbage is an oddity because Lugnaquillia Mountain is very much an outlying station, far away from the main centre of distribution in Cork and Kerry. Some 13.5 km northeast of Lugnaquillia Mountain a rocky escarpment at 557 m overlooking Lough Ouler, near Tonelagee, hosts alpine lady’s-mantle and, together with a site on the Brandon Mountains, Co. Kerry, these are the only localities where the species has been seen in Ireland since 1970. Alpine lady’s-mantle is tall for an arctic-alpine, reaching up to 20 cm. Its leaves, unlike those of its close relative lady’s-mantle, are divided to the base and underneath are silvery grey with hairs. The flowers are small (3 mm) and pale green. Also growing on the Lough Ouler escarpment is alpine saw-wort which belongs to the daisy family. It is a short, stout perennial that looks somewhat like a thistle with fragrant purple flowers in August-September. Both alpine lady’s-mantle and alpine saw-wort were first recorded in Ireland from the mountains of ‘Keri’ by the Welsh antiquarian and naturalist Edward Lhwyd in 1699. Alpine saw-wort has now been reported from 26 sites in Ireland, at altitudes over 300 m. It is thought to be declining.¹⁶

      Gorse, furze or whin, characteristic of the rough grassland or heaths of the lower parts of the Wicklow Mountains.

      A re-survey of the area studied by Pethybridge & Praeger was carried out 50 years later by John J. Moore, champion in Ireland of the study of plant communities using the mathematical and quantitative phytosociological methods of the German botanist Braun-Blanquet.¹⁷ Moore redefined the plant communities and found that they had remained remarkably stable over the years, the main changes being an advance of bracken, extending its range by a maximum distance of 150 m, and to a lesser extent of western gorse, into abandoned farmland. A widespread reduction in the frequency of the woolly fringe-moss in the high land was also observed.

       The Galway and Mayo highlands

      The great metamorphic rock masses of west Galway and Mayo stretch some 120 km from south Connemara to north Erris in one of the wildest and most beautiful parts of Ireland. In the south, the Twelve Bens stand out as rugged steep-sided mountains with quartzite peaks, many of which are higher than 600 m. Although the region is described as the Twelve Bens, there are, as pointed out by Hart, 17 more or less detached peaks from about 457–731 m.⁸ Mica schists appear in the western peaks and through weathering break down to provide the more attractive calcareous soils on which many mountain species thrive in an abundance rarely attained elsewhere in Ireland. To the east of Lough Inagh, defining the eastern boundary of the Twelve Bens, lie the Maumturk Mountains, a large ridge of quartzite, peaking at 702 m. Blanket bogland, characterised by purple moor-grass which grows with extreme luxuriance, dominates the Connemara slopes to about 300 m before giving way to vegetation in which heather is the key species.

      Irish mountains and uplands are invariably bleak, generally bereft of woody vegetation above 300 m. Here, in the neighbourhood of the Killary Harbour, Co. Mayo, the siliceous soils, derived from Silurian slates and shales, offer little opportunity for a diverse vegetation.

      Bengower is one of the most southerly peaks of the Twelve Bens and its summit reaches 666 m. The vegetation of the north-facing slope at 550 m was examined in the early 1960s by Ratcliffe, the first to give a detailed description of the flora of that particular stretch.¹⁸ No remarkable specimens were found apart from the liverwort Adelanthus lindenbergianus, a southern hemisphere species first discovered at Slievemore, Achill Island, Co. Mayo, in 1903 by H. W. Lett – when it was mistakenly named as an endemic, A. dugortiensis – and only known from these two stations and from Errigal and Muckish Mountains, Co. Donegal.

      Praeger wrote that the best ground for the botanist is Muckanaght (654 m) in the centre of the Twelve Bens, where ‘an oasis of schist in a Sahara of quartz’ encourages a ‘very pretty colony of alpine plants’.³ Alpine meadow-rue, purple saxifrage, mountain sorrel, alpine saw-wort, dwarf willow and holly fern grow here. Ever since Wade first published a list, albeit slender, of the flora of Connemara – in which he recorded the first discovery in Ireland of the American species pipewort¹⁹ – Connemara has attracted a continuous procession of distinguished botanists and naturalists. The most extensive botanical investigations of the Connemara mountains were carried out by Hart, whose 1883 paper remains a standard text today.⁸ Colgan followed soon afterwards with a less ambitious work² and Praeger was also a frequent visitor from the early part of this century.³ More recent investigations on mountain plants have been published by Roden²⁰, while Webb & Scannell provide an account of all Connemara plants in Flora of Connemara and the Burren.²¹

      Slievemore, Achill Island, Co. Mayo, in the distance.

       Mweelrea Mountain, Co. Mayo

      The Irish name of this highest mountain in Connacht – An maol riabhach: ‘the grey bald mountain top’ – fits it perfectly. Built of Silurian slates and shales chiefly with sandstones, schists and conglomerates, it presides boldly over a remote corner of southwestern Mayo, overlooking Killary Harbour. To the north are the islands of Clare and Achill; to the east the more stark grey mountain of Ben Gorm (700 m) and the Sheeffry Hills (highest point 762 m). Whilst in many respects a smooth and accessible mountain, Mweelrea has high vertical cliffs on the inland side. As observed by Hart when he visited the summit (814 m) in the summer of 1882, the prospects for alpine plants are raised but not completely fulfilled by ‘the long ranges of precipices, ridges and gullies ending in ravines with sheer sides and dangerous nooks’. Once he got to the top he found the following, amongst other species: St Patrick’s cabbage, starry saxifrage, roseroot, the hawkweeds Hieracium anglicum and H. iricum, bearberry, mountain sorrel, dwarf willow, stiff sedge, tufted hair-grass, alpine clubmoss, lesser clubmoss and quillwort.

      During a visit in September 1961, while examining the cliffs at the head of the great north corrie at nearly 790 m on the east spur of Mweelrea, Ratcliffe discovered the liverwort Jamesoniella carringtonii, widespread in the Scottish Highlands but never previously recorded in Ireland. On Mweelrea it was found growing СКАЧАТЬ