COMMON YARROW, Achillea millefolium L. 1, plant in flower; 2, disk flower; 3, ray flower; 4, flower head; 5, root system. Perennial, reproducing by seed and underground rhizomes. Stems 1 to 2 feet (30 to 60 cm) tall, branching at top, covered with grayish-green hairs. Each crown may produce several stems. Leaves soft, covered with hairs, finely divided, fernlike. Basal leaves longer than those attached to stems. Flower heads small with 5 to 10 white ray flowers and yellow disk flowers, in flat-topped clusters at top of branches. Pink-flowered forms occur rarely. Seed tiny, flat, oblong, white or gray. Found in meadows, pastures, and waste places; not common in cultivated fields. Persists mostly on thin soil where conditions are unfavorable for the growth of more desirable plants. The plant has an offensive odor and bitter taste.