Bog Asphodel, Narthecium ossifragum, growing at Meathop Moss in Cumbria.

It’s December, a time of short days and few flowers (apart from stalwarts like Winter Heliotrope).

It’s good to escape these dark and dreary times for a while and look back at the summer. Something bright yellow should do the trick: Bog Asphodel, Narthecium ossifragum.

In June we visited Meathop Moss in Cumbria, primarily to see Large Heath butterflies. We eventually saw them when the sun came out.

Large Heath butterfly at Meathop Moss, Cumbria. 26th June 2017.

While we were waiting for Large Heaths, we had a look at the plants growing on this lovely lowland raised bog. One of the finest of these was Bog Asphodel.

I first saw Bog Asphodel on the moorlands of Northern Scotland but it is a rare plant in the south and east of England, so it was many years since I’d seen it. It was lovely to see this old friend in all its glory.

Bog Asphodel is a member of the family Nartheciaceae, though at one time it was considered to be part of the Liliaceae (Lily Family) or Amaryllidaceae (which contains plants such as Agapanthus). It is a perennial of wet bogs, where it grows up to slightly more than 1000 metres above sea level. (It has been reported up to 1130 metres altitude in parts of Scotland.) It has a mostly northern and western distribution in the British Isles. It is known from six sites in Norfolk and is found in the Roydon and Wolferton areas, where “it can sometimes be abundant” (Becket & Bull, “A Flora of Norfolk, 1999). Bog Asphodel can also be found in suitable habitats in Scandinavia, the Netherlands, Belgium, Northwest Germany, Western and Central France, Northern Spain and East Portugal.

Bog Asphodel has creeping rhizomes which bear upright, pyramidal spikes of yellow star-like flowers with six petals and six bright reddish-orange anthers from June until August. The leaves are narrow and form a flattened fan around each stem. Individual flowers are lovely when seen up close, but the massed flowers are spectacular, especially in contrast to the browns and greens of their surroundings. After flowering, the plant sets reddish, egg-shaped fruits and these and the stems, which have an orange hue, remain attractive into autumn. There are some lovely photographs of the plant on the Wild Flower Finder website.

The “asphodel” of the plant’s English name comes from its similarity to the White Asphodel, Asphodelus albus, although that plant grows on limy soils around the Mediterranean and is in a different plant family, the Asphodelaceae. “Bog” refers to the plant’s preferred habitat. Other English names include Maiden’s Hair, Moor-golds, Yellow Grass, Bastard Asphodel and Lancashire Asphodel.

The specific name of the plant, ossifragum, means ‘bone breaker’. This refers to the old belief that after grazing on this plant the bones of sheep became brittle. However, it is now thought that the sheep’s brittle bones were caused by a lack of calcium in the soils where Bog Asphodel grows.

Nonetheless, Bog Asphodel really is toxic to livestock, but in other ways.

Lambs will usually eat grass in preference to Bog Asphodel, but where grass is less plentiful they may eat the plant and, as a consequence, develop liver damage and photosensitivity. The photosensitivity occurs especially on unpigmented areas of the skin such as the face, ears and feet. The skin becomes red, hot and swollen and may break. In severe cases, the animals can go blind and the liver damage may be fatal. The condition is known by various names, including “alveld” in Norway, “saut” in Cumbria, “plochteach”, “yellowses” and “head greet” in Scotland and “heddles” and “hard lug” in Northern Ireland. (“Alveld” translates as “elf fire”.)

The website Toxicology.no (“Norway’s portal to natural toxin research”) gives an interesting summary of Bog Asphodel’s toxicity. Different breeds of sheep vary in their susceptibility and the disease is usually restricted to young lambs (two to six months old), and more cases are seen in colder and wetter summers.  Cattle and Elk (Moose) can also show Bog Asphodel poisoning: symptoms in cattle can include anorexia, diarrhoea, melena, dehydration and death.

The standard explanation for Bog Asphodel toxicity is that trisaccharide saponins found in the plant are to blame. Animals that eat green plants break down the chlorophyll they contain into a waste product called phylloerythrin and this is normally excreted from the body. But some of the breakdown products from the saponins in Bog Asphodel seem to interfere in the removal of phylloerythrin from the body. Phylloerythrin can then enter bloodstream and cause a photosensitive reaction where the animal’s skin is exposed to sunlight. The situation is probably more complicated than at first thought: recent research suggests that toxins from fungi or cyanobacteria associated with Bog Asphodel may also play a role.

Humans have used Bog Asphodel as a substitute for saffron and also, in the seventeenth century, as a hair dye. The Herbs – Treat and Taste website reports that Bog Asphodel has been used in the past to treat hernias, coughs and ulcers and inflamed genitals.

I won’t be using it soon and I am happy just to look at this lovely plant. Here is another photograph, viewed from above.

Bog Asphodel from above.