Dog's Mercury

Mercurialis perennis, or Dog's Mercury, is a spring flower found across Europe, but almost absent from Ireland, Orkney and Shetland. It is a hairy dioecious perennial with erect stems bearing simple, serrate leaves. The inflorescence is green bearing inconspicuous flowers in March and April. It is frequently found covering large areas in dense stands as an understorey plant in woodlands, especially, but not exclusively, on calcareous soils.

Dog's Mercury is a poisonous plant; however, boiling or drying can destroy the toxins.

This plant favours alkaline (basic) soils and can be found in abundance in limestone regions particularly in Yorkshire. It also favours deep shade and can survive in semi-shade, however in areas of high light intensity Dog's Mercury will give way to different plants.