LINDISFARNE ORCHID FIELD MEETING

12^th July, 2008

T

he weather en route to the Lindisfarne meeting alternated between drizzle and lashing rain at a miserly 11^oC, more typical of November than July, but we comforted ourselves with the thought that there would at least be some marsh available for the Marsh Helleborines to inhabit.

Julia and I travelled with Richard Milne and Alex Twyford, our newly-recruited Student Representative, and were met at The Snook by Barbara Sumner, Colonel Simon Furness, President of the Berwickshire Naturalists’ Club, and a ranger from Natural England, who introduced the group (now swelled by a further dozen Berwickshire Naturalists) to the remit of Natural England and the botanical delights of Lindisfarne.

The group set off in the rain towards a patch of Schoenus nigricans so large as to be readily visible from space (see Google Earth), alongside which were patches of rather drowned-looking Anagallis tenella and odd plants of Centaurium littorale. Very quickly, orchids were spotted (no pun intended), Dactylorhiza fuchsii in various shades of light and deeper pink, some of which were probably hybrids with the Northern Marsh Orchid (Dactylorhiza purpurella), which was also present. By this time, the Early Marsh Orchids (Dactylorhiza incarnata) were well past flowering and had fattening seedpods. Many individual spotted orchids were of colossal size, up to about 50cm in height. Soon, scattered individuals of the Marsh Helleborine (Epipactis palustris) were encountered, and then much more substantial patches of perfect specimens just about at the peak of flowering were seen in gaps at the edge of the Schoenus patch. This must be one of our most tropical-looking orchids, and the subtle colouring of the flowers really repays close inspection. Nearby, with its feet in water, the Brookweed (Samolus valerandi) (Primulaceae) was present in some numbers, looking at first glance a bit like a crucifer, but with its petals in fives.

Towards the mid-south of the island, we encountered our first Lindisfarne Orchids (Epipactis sancta) surrounded by a chickenwire exclosure to protect against rabbit grazing and trampling. These particular individuals seemed spectacularly large, more than twice the height of the average Marsh Helleborine, but other examples were more on a par. The species was never common, but scattered examples were found in various locations over a wide area of the south of the island, mostly in slightly elevated positions, perhaps a metre or so above the dampness preferred by E. palustris. Close by, growing among Salix repens and again elevated slightly above the wettest slack, was a population of Pyrola rotundifolia var rotundifolia, in a maritime mode unfamiliar to us in Scotland. In such areas, Cladonias were very frequent, sometimes replacing vascular plants as the dominant life-form over many tens of square metres.

Some of the “winter-wet” dune slacks were also flooded on this particular day in July, which impeded progress slightly, but the edges of the flooded areas were spotted with Potentilla (sorry, Argentina) anserina, Ranunculus flammula, Anagallis tenella, Samolus valerandi, Marsh Pennywort (Hydrocotyle vulgaris) and Lesser Clubmoss (Selaginella selaginoides). On the orchid front, occasional late-flowering Dactylorhiza incarnata were seen, together with plenty of D. fuchsii, D. purpurella and a range of hybrids including a patch that looked astonishingly like D. maculata, though this was surely just a botanical coincidence. There were also a number of circular groups of Epipactis palustris, their perimeters delineated by flowering individuals. Richard explained to the group that the species spreads rapidly by means of creeping rootstocks, quickly forming clonal populations, and the individuals in these orchid fairy rings were hence probably all genetically identical.

In search of Anacamptis and Gymnadenia, the group walked across dune slacks containing spectacular populations of Epipactis palustris to the north of the island, but failed to find either. Occasional well-camouflaged plants of Listera ovata were present, and Richard found a single individual of Coralroot Orchid (Corallorhiza trifida) among the Salix repens. In the drier dunes of the north Echium vulgare was frequent, and Common Valerian (Valeriana officinalis) but alas, no orchids. Ragworts (Senecio jacobaea) were being systematically stripped of their leaves by hordes of Cinnabar Moth caterpillars. Nearing the north edge of The Snook we came across areas of old shingle which may be the remains of a raised beach, whose flat and dry habitat contrasted strongly with the dune slacks further south, and which supported luxuriant patches of Restharrow (Ononis repens).

As we headed back, a wet slack with standing water contained a superb stand of the Common Spike-rush (Eleocharis palustris) again with Samolus and Ranunculus flammula. Close to the house, more areas of old shingle supported substantial populations of Centaurium littorale, growing as dwarfed plants in association with dwarfed Galium verum, Gentianella amarella ssp. septentrionale and lichens. Selaginella selaginoides and Sagina nodosa were also found in moist turf at the edge of this area, and the grass by the pathside provided Astragalus danicus with superb fruiting bodies. Here also a Garden Tiger Moth, rendered soporific by unseasonal cold, was much photographed. Returning to the car park, the group’s attention was drawn to a wet area containing predominantly salt-marsh species, including Glaux maritima, Juncus gerardii, Triglochin maritima, Armeria maritima, Plantago maritima and Aster tripolium. The area seemed too far from the sea for submergence in sea water to be likely, or even possible.

The Harebell or Scottish Bluebell (Campanula rotundifolia) was just coming into flower, though many flowering stems still had a long way to go. In one area, Julia and I had previously encountered considerable variation in flower colour and form, and it was interesting to note that the variation still persists. White, pink and lilac colour variants occur there together with variants in the intensity of blue, the corolla tubes of various lengths and with the tips sometimes incurved instead of the usual outcurved, campanulate form. Forms with 6-, 7- and 8-fold symmetry are also present. Nearby were plants of Pinguicula vulgaris in fruit, and one patch of what appeared to be the garden form of Fragaria vesca (“Alpine Strawberry”).

In summary, The Snook served up a richly rewarding botanical feast, and if that isn’t adequate compensation for a bit of wet and unseasonal cold, I don’t know what is. The only downside to the whole day was the task of removing pirri-pirri-bur from every item of clothing and car upholstery containing anything even vaguely resembling Velcro loops. The group from the Berwickshire Naturalists’ Club were extremely enthusiastic and unbowed by the dreadful weather, and a return match in our neighbourhood might be greatly appreciated by both sides.

Chris Jeffree, Edinburgh

Note: The day after our excursion Kathy Bell, a volunteer garden guide at RBGE, visited Lindisfarne with her family and found the Lesser Butterfly Orchid (Platanthera bifolia), which had never before been recorded for the Island, bringing the number of Orchid species recorded there to 11.