Tuesday 12 August 2008

Ferns


I am always amazed that humans got where they are today since they are so badly adapted to any extreme of temperature away from 50-70deg F and are particularly useless in rain. Other animals are out there all the time not battering an eyelid at the rain, but we cower and reach for the Sunday supplement. Although it may not be the Tourist Boards best slogan, on the West coast of Scotland we live in a temperate rainforest zone. We have lost pretty much of our original wet forest in the UK, but examples are scattered up the western seaboard. It is a pity that we don’t have old growth forests left, since these could act as blueprints to shape the future, but in other parts of the world, such as the Pacific Northwest, they have some fine, albeit fragmented old growth forests.
Living in a wet woodland is a difficult place to inhabit, but at least the climate is fairly constant, no great extremes of heat or cold. It is not the prime habitat for showy flowers or butterflies, except in glades, but it is a great place for the more esoteric species such as lichens, mosses and ferns. Coming back to Arran after a while away it is a real treat to see the luxuriance of the vegetation especially when one has been to more arid climes. Ferns can be important ecologically as pioneer species of bare ground and their very presence with help to maintain the humidity of a woodland. In our areas cleared of Rhododendron ponticum, it is heartening to see ferns come back into the barren soil and I was delighted to find Royal fern, the most handsome of our native ferns growing down by the Merkland burn as a partner to our smallest fern, Tunbridge Filmy-fern
Ferns are associated with damp conditions because they need water in order to complete their reproductive processes. The sexual processes of a fern are rather miraculous and improbable and in the past were explained away by the thought process that they must have invisible flowers. Fortunately these invisible flowers could be collected at Midsummer’s eve and used to make one invisible.
An Arran naturalist expressed the opinion that “life’s too short for ferns”, meaning that they are impossible to identify. Like everything in natural history, it depends on how far you want to go, and when you consider that there are perhaps only a dozen or so common ones to get to grips with, it doesn’t sound too daunting. The fern world is a friendly place and those in the know have produced a fantastic guide to ferns in the AIDGAP series, which has no nonsense id tips, great drawings and photos.
Of course Bracken is known to all and demonised by everyone, but at 40mph it is quite difficult to tell the difference between this and other ferns, and even more difficult if you are in a Helicopter spraying Asulox from a great height. The danger in the state sponsored pteridocide craze is that the herbicides can’t differentiate between Bracken and any other fern, so all the others are killed as well. At North Glen Sannox, the hillside appears to be covered in Bracken, but closer inspection reveals a whole array of flowers and big patches of lemon-scented , Beech and Oak Fern. Arran is also home to the Killarney fern, and although the sites of its occurrence are known, how do we know that there aren’t other sites that could be damaged by spraying?