Achillea millefolium - Common Yarrow A beautiful floral herb, this weed is often overlooked or mistakened for another more common species, Queen Anne's lace (or wild carrot). With thick stems, multiple small, narrow leaves, and bundles of small white or purple flowers, you won't overlook this one anymore if you know what it looks like. Yarrow is an incredibly versatile herb. Historically, it's been used to treat cystitis (bladder infection), digestive sluggishness, as an astr