While May is often the sunniest month in the north and west, it can be dominated by cold easterly winds, so spring comes late to the machair. Dune grassland or links, on the east and south coasts of the mainland, might support hundreds of different plants, yet machair – so much further north – has rather fewer. Nonetheless, a typical patch of machair can look surprisingly rich, with up to 45 species in any metre square.
Once the pasture blooms, it presents an astonishing riot of colour for which the machair is justly famous. It is this beauty that draws many tourists to the Northern and Western Isles each summer and inspired generations of Gaelic bards.
Sa mhadainn shamhraidh nuair chinneas seamrag, `S i geal is dearg air a`mhachair chomhnard. Is lurach, blathmhor a lusan sgiamhach, Fo dhriuchd na h-iarmailt `s a`ghrian gan oradh. On a summer morning when the clover burgeons Red and white on the level machair, Lovely the plants with their many blossoms, Fresh with the dew and shining in the sun. Oran nam Priosanach
Sa mhadainn shamhraidh nuair chinneas seamrag,
`S i geal is dearg air a`mhachair chomhnard.
Is lurach, blathmhor a lusan sgiamhach,
Fo dhriuchd na h-iarmailt `s a`ghrian gan oradh.
On a summer morning when the clover burgeons
Red and white on the level machair,
Lovely the plants with their many blossoms,
Fresh with the dew and shining in the sun.
Oran nam Priosanach
Early in the season daisies dust the machair like snow but, in places, they can be a sign of heavy grazing. Other white flowers are eyebrights and wild carrot, with cotton grass in wet areas. In June, yellow is the dominant colour, from buttercups, vetches and bird’s foot trefoil. On damper ground, silverweed, yellow rattle, and marsh marigolds thrive. Orkney machair has the rare limestone bedstraw. Red and purple become the main colours later in the summer; red clover and ragged robin, with self heal in damp grassland, while field scabious and autumn gentian are unusually common.
Orchids are particular machair highlights. The rare pyramidal and fragrant orchids both occur in the Outer Hebrides. There is a particular Hebridean type of spotted orchid while a small stretch of North Uist has its own variety of marsh orchid, Dactylorhiza majalis scotica, found nowhere else. Irish machair can boast bee orchids, its own variety of marsh orchid and the dense-flowered orchid from the Mediterranean.
There are fewer plants where machair meets moorland, on the so-called ‘blackland’, and here the croft buildings, enriched pasture and hay meadows are found. On Coll and Barra, however, small patches of damp, peaty pasture or marsh grazed by cattle are home to one of the rarest orchids in Europe; Irish lady’s tresses. It is mainly a North American species and how it came to colonise the remote western coasts of Scotland and Ireland is still being debated. One theory is that the tiny seeds were transported on the muddy feet of migrant wildfowl such as white-fronted geese.
. . . these sands produce crops of barley, oats, rye and potatoes, or of natural grass and wild clover, far beyond what a stranger would expect. They then assume a variegated and beautiful dress, scarcely yielding in colours or perfume to any fields in the kingdom; and being of great extent, they afford a prospect of riches and plenty equalled by no other of the Western Isles.
It may be the presence of stock that encourages plants such as orchids, but the real display of machair flowers is greatly enhanced by another agricultural activity; cultivation. This requires the control of grazing; township regulations, on the Uist machair for instance, ask for stock to be removed from unfenced areas by early May. With Uist machair often flooded in wet winters ploughing cannot begin much earlier, yet the sandy soils do dry off quickly.
Horse-drawn or cockshutt ploughs do not dig as deep as modern machines, reducing the risk of wind erosion and helping seeds to germinate. Management recommended by Environmentally Sensitive Area (ESA) schemes insist that crofters complete sowing and harrowing by mid-May, in order not to destroy the early clutches of oystercatchers and ringed plover that like to nest on bare ground exposed by the plough.
Tiree machair (nearly half of the island’s area) is not normally cropped; perhaps because the crofting area further inland is fertile and less rocky, and so more easily ploughed. Cultivation has all but ceased in Barra, Harris and Lewis but it is a requirement of any crofter entering the Uists ESA that 15% or more of the machair share is cropped. Traditionally the area was cultivated on a 2 or 3 year rotation so that no more than half the arable machair will come under the plough at any one time.
With generous amounts of seaweed (the ESA recommends 40 tonnes per hectare), lime-rich machair soils are relatively productive yet they can be rather low in some essential nutrients and trace elements such as copper, cobalt and manganese. In the past livestock were able to make up some of this deficiency while grazing on the hills in summer, but now the animals tend to be kept in fenced areas around the croft so mineral supplements may be required.
Nutrients wash out easily from sandy soils, so artificial fertilisers tend to be ineffective; this limits the crops that can be grown. Only the older strains of small oats and rye will thrive, the latter coping particularly well with the dry conditions as it has strong stalks that resist the wind. Small oats grow quite well in competition with wild flowers which – if the crop is intended as anything other than cattle fodder – would otherwise be condemned as weeds. It is, therefore, not practical to consider expensive herbicide treatment. Early in the season, cereal crops are dominated by corn marigold or charlock, with bugloss, field pansy and cornsalad.
In the first year of fallow, wild pansy, poppies, creeping buttercup and storksbill can flower, clover and red fescue coming through in the second year.