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Environment and Wildlife

Hemlock Water Dropwort

Hemlock Water Dropwort: Another noxious plant

Published: 28 April 2023

Hemlock Water Dropwort

Hemlock Water Dropwort is always found growing close to water.
The most poisonous plant in the UK and very common along most of our waterways.

Leaves: Bright green and shiny, a bit fern like with two to four pinnate divisions, the whole looking triangular in shape.

Flowers: A collection of small white flowers arranged in an umbel.

Seeds: Small brown rugby ball shaped seeds in clusters replacing the flowers.

Stem: Bright green, hollow, grooved, hairless, shiney and up to six feet tall. When cut the stem exudes a staining yellow liquid.

Roots: The root is said to taste pleasantly like parsnip before poisoning the consumer.

Habitat: Very common in damp areas including marshes, lake, river and stream sides or along ditches. Can be found several metres inland from water sources.

Other Facts: The term sardonic grin comes from the grisly practice in Phoenician Sardinia of disposing of criminals and old people using Hemlock Water Dropwort. The poison acts by constricting the muscles causing death by asphyxia which also causes a rictus like death grin, the sardonic grin.
Hemlock Water Dropwort is the most poisonous plant in the UK and all parts of it are poisonous, it is reported that death can occur in as little as a couple of hours after ingestion.
Hemlock Water Dropwort is in the Apiaceae family, one of great interest to foragers as the family contains many fine edibles and a good handful of deadly poisonous species.


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