Meadow yellow

Meadow yellow
Bulbous Buttercup (Ranunculus bulbosus) in a Devon meadow

Thursday, 8 March 2012

Spurge-laurel - a healthy pungent purge or scourge?

Very few plants put energy into flowering in the winter due to the cold and lack of sunshine and pollinators. There are some obvious exceptions such as Snowdrops and Winter Aconites. Less obvious is the evergreen shrub, Spurge-laurel (Daphne laureola) which I spotted inadvertently last week in one of our local hedgerows. The origin of the Latin name Daphne apparently comes from the water nymph whom the Gods turned into a laurel-bush to hide from the advances of Apollo (SAPS, 2012). Well in keeping with concealment you would be forgiven for not spotting its flowers, with petals absent and small camouflaged yellow-green sepals. The plant flowers appear from January, a welcome source of nectar for early emergent moths and bees attracted by their strong scent rather than visual cues. But don’t let the sweet fragrance fool you – all parts of a Spurge-laurel plant are poisonous to humans, particularly the bark and berries. It can cause stomach pain, nausea, vomiting, bloody diarrhoea, delirium, collapse and death; even external contact between plant and skin can cause blistering. (Eland, 2012). Some tribes in northern Africa still use a bark extract to poison fish (Eland, 2012). This all serves a useful service for the Spurge-Laurel, as its production of powerful toxic compounds such as coumarin results in a “well defended plant” with very few animals able to eat it (Alonso, 2009).

Interestingly it is not universally toxic to animals; for instance the black berries are eaten by birds like greenfinches without any harm (SAPS, 2012), and in the past used as a veterinary cure for horses (Eland, 2012). It has also been used occasionally in the past for medicinal purposes, such as folk treatments for cancer, toothache and rheumatism (Eland, 2012). Johnson (1856) refers to a “decoction of the root and bark being recommended for children afflicted with worms”, but goes on to warn that “it should never be used, being one of those remedies that can only be employed at the risk of life”. He continues with a more strident note –
“The Lady Bountiful of the village would do more good by confining her benevolent practice to the issue of nourishing food and warm clothing, where necessary, than by trying to combat disease by remedies of which the action is equivocal, if not, as in this instance, dangerous in the highest degree.

In modern times opinion of Spurge-laurel very much leans towards Mr Johnson’s – well at least botanically rather than his gender insinuations.

Alonso, C., García, I.M, Zapata, N. and Pérez, R.(2009) Variability in the behavioural responses of three generalist herbivores to the most abundant coumarin in Daphne laureola leaves. Entomologia Experimentalis et applicata, 32(1):76-83
Eland, S. (2012) [online] Plant Biographies http://www.plantlives.com/docs/D/Daphne_laureola.pdf  [Accessed 7/03/12]
Johnson, C. (1856) British Poisonous Plants. London: Taylor & Francis.
Science and Plants for Schools (SAPS) (2012) [online] http://www-saps.plantsci.cam.ac.uk/trees/laurels.htm [Accessed 7/03/12]


3 comments:

  1. I hoped you washed your hands after touching the spurge - It sounds deadly!

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  2. Not immediately - actually I did feel unwell at the weekend!

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  3. I want to try fishing with this, it sounds so cool!I'll be careful not to consume any myself however...

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