Yarrow

Yarrow is a hardy perennial broadleaf weed that thrives in dry, nutrient-poor soils and low-maintenance turf areas. Known for its feathery leaves and clusters of white flowers, it can be both ornamental and invasive. In lawns, yarrow becomes a persistent nuisance because of its deep root system and tolerance to drought, mowing, and poor fertility. Once established, it spreads aggressively through underground rhizomes.

How to Identify

Yarrow forms dense mats of finely divided, fern-like leaves that are soft and aromatic when crushed. The leaves are alternate, narrow, and deeply dissected, giving them a feathery appearance. Its stems are slender and upright, typically reaching 6–24 inches tall. In late spring to summer, flat-topped clusters of small white to pinkish flowers appear. The plant reproduces by both seed and creeping rhizomes, making it difficult to eradicate once mature.

Lifecycle

Yarrow is a perennial weed that grows actively in spring and fall but can persist year-round in mild climates. It overwinters as a rosette and spreads during the growing season through underground stems. New shoots emerge from the root system, forming colonies that can quickly overtake thin or neglected turf.

Prevention & Control

Effective control requires addressing both surface growth and the deep rhizome system. Hand-pulling or shallow cultivation rarely eliminates yarrow completely, as fragments of root readily regenerate. Broadleaf herbicides containing 2,4-D, dicamba, or MCPP provide good control when applied during active growth. Maintaining a dense, well-fertilized turf discourages reinfestation. Aeration and overseeding can help strengthen turf competition.