Bog Asphodel

One of the key habitats of Dartmoor is the Blanket Bog and living in the plant communities of these areas is the Bog Asphodel. The plant is classified as a ‘Key Indicator Species’ for Blanket Bogs, this basically means it; “is a species that has a disproportionately large effect on its environment relative to its abundance. Such species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community.” – online source – HERE.

There are two habitats on Dartmoor where Bog Asphodel can be found, as noted above in the blanket bogs and also the valley mires. Although classed as an asphodel the bog asphodel actually belongs to the lily family. The plant produces a network of underground stems, or if you like rhizomes, from which it grows but in addition the Bog Asphodel also produces seeds. When in flower the Bog Asphodel displays anything from six – twenty  star shaped flowers along with six hair covered stamens per stem.  The anthers (pollen bearing part of the stamen) are a distinct rusty orange coloured  whilst the flowers are a vivid yellow colour. These appear around about June through to July and as the flower dies off the stems slowly turn a deep saffron colour. Many of Dartmoor’s topographical writer wax lyrical about the plant in autumn and describe bogs burning with asphodel. An average size for the flowers heads would be something in the order of ten centimetres which make for a bold display.

Over the centuries the Bog Asphodel has been used as a yellow dye which could well date back as far as the Iron Age, a hair dye and also in cooking as a cheap substitute for saffron.

Currently there are moves afoot that go by the name of the ‘Dartmoor Mires Project’ whose purpose is to restore Dartmoor’s shrinking blanket bogs. If successful it should mean in theory that once the bogs re-establish themselves then so too will their associated flora, including the Bog Asphodel. Yippee we all shout, greater amounts of CO2 will be stored in the peat thus helping to lessen the effects of climate change. The local water supply will be improved and the bogs will be festooned with thriving communities of Bog Asphodel.

However, ‘every rose has its thorn’ – the Latin word ossifragum roughly translates as ‘bone breaker’, a term given the plant for the early belief that if sheep grazed on it their bones became brittle. In later years this idea was dismissed as it was considered that the sheep’s brittle bones were caused by a calcium deficiency brought on by grazing on poor, marshland vegetation. Breathe a sigh of relief, the Dartmoor flocks can graze in safety but make it a very short sigh because the Bog Asphodel has another, much sharper thorn as the farmers of northern  England are finding out.

Up north there are also vast tracts of blanket bog on the fells where the Bog Asphodel or ‘Bastard Asphodel’ as they call it is thriving along with a disease called ‘Saut’. By no means is this problem  restricted to Britain but also can be found in Europe, the Norwegian farmers call it ‘elf fire’ which is a far more apt name. The disease appears mainly in first season lambs and occurs anytime from late Spring but can also be found in older sheep. The effects are quite dramatic and take on the form of severe sunburn visible on the animal’s head, ears and along the their backs. The problems start when the ears become hot and then droop down, this is followed by intense itching and pain. Fluids then suppurate from the affected area which leads to infection and in some cases the ears actually drop off. Additional problems can be blindness caused by damage to the eyelids, jaundice, liver failure and death. So how does the Bog Asphodel cause these problems? In normal circumstances when an animal digests plants the chlorophyll produces a poison which in a healthy liver will be neutralised. However, the Bog Asphodel contains toxins called Saponins which it is thought causes liver damage by blocking up the bile ducts. This then leads to the toxins being absorbed into the blood stream instead of being harmlessly disposed of as would happen in a healthy liver. Once in the blood stream any areas of the sheep that are not covered by wool becomes photosensitive which results in the symptoms mentioned above. The only treatment is the use of antibiotics to reduce any infection and anti-inflammatories to ease the pain and remove any affected animals from direct sunlight. It seems that the severity of the problem varies from year to year but on some farms it can result in at least a 10% mortality rate. In Norway where the problem is much worse the famers can lose anything up to 40% of their young lambs. New research is also finding that Saut can also cause kidney failure and a present problems in cattle. The first step towards adverting problems is some in-depth research into the disease because the link between Bog Asphodel and Saut is still not fully understood.

On the plus side, another chemical found in Bog Asphodel is aglycone which is currently be investigated for possible cancer treatments. In the past the plant has also been used for treating hernias, coughs, ulcers and believe it or not, inflames genitals – which in light of the above effects might not be a good idea for naturists to use.

It must be said that as yet Saut is not a problem on Dartmoor, there is some thinking that the disease could effect white face sheep more than black faced ones. The majority of sheep grazing Dartmoor are black faced so it could well be the possibility of it becoming a prevalent is lessened.

The Bog Asphodel does provide a good example of what can happen when nature conservation comes head to head with agricultural practices. On one hand you have the various ecological schemes which for varying reasons are promoting the restoration of blanket bogs through SSIs and ESAs etc. In order to monitor and assess the success of these schemes the Bog Asphodel play an important role and so is a welcomed species. Then you have the sheep graziers whose animals sometimes pasture in these areas having the problem of Saut. Elsewhere in the country Natural England have suggested that the farmers keep their livestock away from areas where the Bog Asphodel thrives at the height of the grazing season. This is all well and good if enough alternative pasture is available which in some cases proves impossible. After all said and done that is one of the main reasons why livestock are pastured on the moors. I suppose one could argue that a few sun burned sheep are a small price to pay for controlling climate change, water quality etc but try telling that to the farmer whose livelihood depends on healthy stock. The market price for lamb at the moment is averaging at around about £1.60 a kilo which when the weight of a good sized animal (45kg) comes to a considerable sum.

So next time you are out on the moor and see a colourful yellow and orange spiked carpet on the edge of a bog just remember what it could do to the resident sheep. One last point, should Saut become a serious problem on Dartmoor maybe it could be called ‘Piskie Fire’ in light of the Norwegian name of ‘Elf Fire’?

Finally, my thanks to Keith Ryan for letting me use his splendid photograph of the Bog Asphodel which truly shows the magnificent splendour of the plant in its natural Dartmoor setting.