Sea wormwood likes salty ground, so can be found in coastal areas and in salt marshes along with marsh samphire. It is a close relation of wormwood, Artemisia absinthum, sweet wormwood, Artemisia annua, mugwort, Artemisia vulgaris, tarragon, Artemisia dracunculus, southernwood, Artemisia abrotanum, field southernwood, Artemisia campestris and Artemisia cina known as the producer of Levant wormseed among others. It is a member of the daisy Asteraceae or Compositae family.
It is sometimes referred to in Britain as Old Woman, with southernwood being it counterpart, the Old Man. This is because the plants resemble each other.
Sea wormwood is a hairy plant with fine cottony hairs growing all over it. It is native to Europe including the British Isles, and parts of Asia including Pakistan. It flowers between August and September growing to heights of around two feet tall. A synonym for the genus is Seriphidium maritimum.
As it is closely related to wormwood, which is poisonous in large amounts, it is likely that the same applies to this plant. Some people are affected just by the smell of the plant and suffer from headaches and nervous agitation. However the leaves are edible and have been used as a flavouring agent.
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The leaves and flowering tops are used for worms and also as an antiseptic for external use, and to relax muscles cramps and to stop spasms. They have also been used to calm nervous irritation, reduce flatulence, promote the menstrual flow, to aid digestion and for fevers.
Traditionally the plant has been harvested when it comes into flower and dried for later use. The flowers which are closed and newly opened contain the vermicide, santonin.
The growing shoots of the plant are said to repel insects and mice and other rodents, and were once used as a strewing herb. An infusion of the shoots and aerial parts of the plant can be used to discourage garden pests such as insects and slugs.
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In traditional Arabic medicine the leaves are said to have cooling properties and the powdered plant is administered for worms. The plant’s twigs are also used as a broom.
The chloroform extract of the root has been shown to have anti-malarial properties, and it has been traditionally used for this in the Pakistani province of Khyber Pakhtoonkwha (formerly the North West Frontier Province).
Some people use the plant to relieve pain, and smoke it although they have reported having vivid dreams under its influence and have found it “stimulating.”
Writing in the 17th century, the English herbalist, Nicholas Culpeper has this to say about it. (The annotations are mine.)
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*Roman wormwood referred to by Culpeper is Artemisia pontica.
†John Parkinson (1567-1650) apothecary to Charles I of England and also a herbalist.