Yarrow (Achillea millefolium) is a native North American plant that’s popular with pollinators and practically care-free, making it perfect for borders, ground covers, and open meadows. Yarrow is an herb. The above ground parts are used to make medicine. Yarrow is used for fever, common cold, hay fever, absence of menstruation, dysentery, diarrhea, loss of appetite, gastrointestinal (GI) tract discomfort, and to induce sweating. Some people chew the fresh leaves to relieve toothache. When taken by mouth: Yarrow is commonly consumed in foods. But yarrow products that contain a chemical called thujone might not be safe. Thujone is poisonous in large doses. Yarrow is possibly safe when taken in doses of 250-500 mg daily for 12 months. It was one of the herbs dedicated to the Evil One, in earlier days, being sometimes known as Devil’s Nettle, Devil’s Plaything, Bad Man’s Plaything, and was used for divination in spells.Yarrow is generally considered safe to use medicinally but possible side effects may include: Drowsiness. Increased urination. Skin irritation when used topically (such as for wound healing). What is the herb yarrow good for?!Is the yarrow poisonous to humans?!Is yarrow an annual or perennial?!Why is yarrow called devil’s nettle?! Achillea millefolium, commonly known as yarrow (/ˈjæroʊ/) or common yarrow, is a flowering plant in the family Asteraceae. It is native to temperate regions of the Northern Hemisphere in Asia, Europe, and North America. It has been introduced as a feed for livestock in New Zealand and Australia. In New Mexico and southern Colorado, it is called plumajillo (Spanish for ‘little feather’) from its leaf shape and texture. In antiquity, yarrow was known as herba militaris for its use in stanching the flow of blood from wounds. Other common names include old man’s pepper, devil’s nettle, sanguinary, milfoil, soldier’s woundwort, and thousand seal.