Achillea millefolium

Yarrow Identification & Control

Yarrow, botanically known as Achillea millefolium, is an exceptionally common, highly persistent perennial broadleaf weed in the Asteraceae family. Native to the Northern Hemisphere, it is a frequent nuisance in dry home lawns, pastures, and garden beds. Growing up to 3 feet tall, it is easily recognized by its highly distinct, finely divided, feathery fern-like green leaves, and produces flat-topped clusters of tiny, daisy-like white-to-pink flowers. It spreads aggressively via a tough network of underground rhizomes. While highly valued in herbal medicine, Yarrow contains volatile oils and alkaloid compounds that are toxic to dogs and cats, causing vomiting, diarrhea, and skin photosensitivity.

Sunlight Full Sun to Partial Shade

Watering Tolerance Low to Moderate

Soil Adaptability Dry Sandy / Sterile Loam / Poor Clay

Growth Temp 5°C - 35°C

Danger / Toxicity Pet Toxic (Vomiting & Photosensitivity) / Creeping Rhizomes

Botanical macro photography of Yarrow (Achillea millefolium) - Plant AI care and control database

How to Identify Yarrow

An upright perennial with finely divided feathery green leaves, flat-topped clusters of tiny white-pink daisy flowers, and a strong aromatic scent.

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Feathery Fern-Like Leaves: Alternate green leaves are deeply divided into hundreds of narrow, needle-like segments, showing a highly distinct feathery or fern-like appearance.
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Flat-Topped Flower Clusters: Large, flat-topped, umbrella-like clusters (corymbs) composed of hundreds of tiny, 5-petaled white-to-light-pink flowers.
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Strong Aromatic Scent: Crushing the feathery foliage releases a highly pungent, sweet, medicinal, and spicy aromatic scent.

💡 Herbal Legend: Yarrow's scientific name *Achillea* comes from the Greek hero Achilles! According to legend, he used yarrow leaves to stem the bleeding wounds of his soldiers on the battlefield, earning it the common nickname 'woundwort'.

Complete Care & Management Guide

Access highly technical, scientific management directives to control or cultivate Yarrow effectively.

Extremely drought-tolerant. It thrives in dry, baked, and water-starved lawns due to its extensive creeping rhizome system, outcompeting thirsty turf grass in dry summers.

Resistant to mowing. Regular mowing will clip the upright flower stalks, but the feathery basal leaves lie very close to the soil, surviving easily.

Thrives in nutrient-poor, sandy, and dry clay soils. Applying nitrogen-rich organic lawn fertilizer helps grass grow densely, shading out yarrow rosettes.

Requires Full Sun but tolerates partial shade. It easily creeps under ornamental garden borders and invades sparse shaded lawns beneath tree canopies.

Adapts to dry sandy loam, compacted poor clay, roadsides, and disturbed fields. It struggles in wet, saturated organic bogs.

Spreads aggressively by creeping stolons and seeds. Stems root at every node touching the soil, while mature seed heads produce thousands of durable seeds.

Extremely cold-hardy perennial. Foliage turns a dark green-bronze but stays evergreen in mild winters. In harsh freezes, it dies back but rhizomes survive easily.

Features a short, branched taproot with a dense network of fibrous lateral roots. It is exceptionally easy to hand-pull due to its shallow root anchor.

Occasionally targeted by aphids, but pests rarely slow its aggressive colonization.

Subject to **Powdery Mildew** under humid autumn weather, though diseases rarely kill the extensive root crown system.

To control Yarrow organically, raise your lawn mowing height to help grass shade the soil, and manually dig out the creeping white rhizomes in early spring.

Common Diseases & Treatment

Pet Yarrow Dermatitis

Symptoms: Symptoms: Dogs chew on yarrow leaves, leading to severe drooling, vomiting, diarrhea, and localized skin photosensitivity/redness.

Action: Action: Flush the mouth and skin with clean water. Keep the pet out of direct sunlight for 24 hours, and consult a vet if vomiting persists.

Lawn Feather Choke

Symptoms: Symptoms: Cool-season grass is replaced by dense, velvety green mats of feathery yarrow leaves that resist mowing.

Action: Action: Apply nitrogen-rich organic lawn fertilizer to boost turf grass growth. Hand-rake and extract the creeping white rhizomes.

Frequently Asked Questions

Is Yarrow toxic to pets like dogs and cats?

Yes. Yarrow contains volatile oils, monoterpenes, and alkaloids (such as achilleine) which are toxic to dogs, cats, and horses. Ingestion causes vomiting, diarrhea, hyper-salivation, and skin photosensitivity.

How does Yarrow survive frequent lawn mowing?

While mowing cuts down its upright flower spikes, its soft, feathery basal leaves grow in a flat rosette extremely close to the soil surface. This prostrate growth habit allows it to escape lawn mower blades completely.

What is the best way to get rid of Yarrow in a lawn organically?

You can manually rake the lawn with a thatch rake to lift the creeping stems, then dig out the shallow white rhizome chains completely. Additionally, raising your lawn mower height to 3 inches and applying high-nitrogen fertilizer will help the turf grass crowd it out.

Can Yarrow be used as a ground cover?

Yes, in dedicated native gardens where it is allowed to spread, it acts as an outstanding drought-tolerant lawn alternative. However, its aggressive rhizomes and self-seeding nature make it difficult to contain.