What Are Yarrow Weeds?

Identification

• Yarrow features a fine, featherlike foliage resembling a fern and reaching 24 inches in height. The rosette leaf structure is similar to a wild carrot but is distinguished by a rhizome system of fibrous roots. Bloom occurs from March through September. Clusters of small white, yellow, pink or red flowers create flat-topped flower heads at the end of the stems. The resulting fruit is oblong and flat, reaching 1/12 inch in length. Each fruit, called an achene, holds one seed.

Invasive Weed

• The ability of yarrow to reproduce through creeping underground rhizomes allows it to spread into turf, gardens and pastures. Both wear and drought tolerant, yarrow may not be easily identified in areas frequently mowed. To help control the spread of yarrow, improve turf growing conditions and mechanically remove yarrow weeds in spring before they bloom. Broad-leaved herbicides, such as 2,4-D and dicamba, manage the weed effectively when applied during periods of active plant growth in late spring through early fall.

Medicinal Purposes

• Yarrow is a popular herb in European folk medicine. Traditional uses include topical application for wounds and bleeding, ingesting for digestive complaints and use as a tea for anxiety or insomnia. According to the University of Maryland Medical Center, yarrow contains chemicals known to improve digestion and relieve stomach and menstrual cramps. The flowers, leaves and stems are collected just before or during bloom. Yarrow may also be purchased from retailers as a dried herb, in capsule or tablet form or as a liquid extract.

Naturalized Benefits

• Yarrow occupies many dry, poor areas. For example, the Great Basin area values yarrow as a beneficial plant. Sheep, deer and sage grouse chicks graze on yarrow. Yarrow helps keep soil from eroding and can grow rapidly in at-risk areas, such as land damaged by wildfire. Once other natural grasses establish in the area, the yarrow diminishes.

Landscaping and Garden

• Gardeners often use yarrow in borders, containers and in mass plantings. The flat flower clusters and soft foliage provide a contrast to other plants in a garden and make an interesting addition to cut flower arrangements. Yarrow does not burn easily, making it an ideal fire barrier planting for properties or at-risk areas. High drought tolerance and suitability to poor soils allow for the use of yarrow as a ground cover in a variety of locations.