Melilotus officinalis (Common melilot). Also known as Sweet clover

Plant has high pollen content and favoured by bees. Flowers have been used to perfume snuff and pipe tobacco. Contains coumarin. Haemorrhage by grazing animals following ingestion led to the discovery and extraction of dicoumarol, marketed as warfarin - an oral anticoagulant that interferes with the metabolism of vitamin K. It is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. Plant clump with treoil leaves on tall stems. Has early flower buds.