Summary ²

Achillea millefolium, commonly known as yarrow /ˈjæroʊ/ or common yarrow, is a flowering plant in the family Asteraceae. It is native to temperate regions of the Northern Hemisphere in Asia, Europe, and North America. It has been introduced as a feed for livestock in places like New Zealand and Australia. However, it is a weed in those places and sometimes also in its native regions.

Yarrow is a strongly scented, downy perennial herd with long creeping stolons; upright, usually unbranched stems up to c.45cm tall. Leaf blades are 5-15cm long and up to 25mm wide. They are lance shaped and feathery in appearance and finely and very deeply dissected (2-3 pinnate). Lower leaves on short (≤ 5mm) stalks, upper leaves are stalkless and shorter. Flowers consist of flattened clusters of many (> 25) small (4-6mm across) compound flowers; each compound flower formed of c.5 white (rarely pink) outer florets and several white/cream inner florets. Each fruit is dray, flattened, thin-walled, tiny (c. 2 x 0.8mm), hairless and containing a single seed; without pappus; wind dispersed; seeds may persist in the soil for 5 years or more. Often found in disturbed ground around buildings and in wetter areas of 'Acaena herbfield'.

Distribution ³

Grytviken and Husvik

Comments ⁴

Yarrow could be mistaken for sneezewort but the latter has undivided leaves and compound flowers over 1cm in diameter. When not in flower yarrow could be mistaken for feathery buttonweed however the latter has less feathery leaves that are much shorter (<5cm).

Sources and Credits

1. (c) Steve Guttman, some rights reserved (CC BY-NC-ND), http://www.flickr.com/photos/24013640@N02/3683708823
2. Adapted by stuwhiterod from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Achillea_millefolium
3. (c) Kelvin Floyd, some rights reserved (CC BY-SA)
4. (c) stuwhiterod, some rights reserved (CC BY-SA)

More Info

• iNat taxon page
• African Plants - a photo guide
• Atlas of Living Australia
• Biodiversity Heritage Library
• BOLD Systems BIN search
• Calflora
• CalPhotos
• Catalogo de Plantas y Líquenes de Colombia
• eFloras.org
• Flora Digital de Portugal
• Flora of North America (beta)
• Global Biodiversity Information Facility (GBIF)
• Go Botany
• HOSTS - a Database of the World's Lepidopteran Hostplants
• IPNI (with links to POWO, WFO, and BHL)
• Jepson eFlora
• Maryland Biodiversity Project
• NatureServe Explorer 2.0
• NBN Atlas
• New Zealand Plant Conservation Network
• OregonFlora.org
• SEINet Symbiota portals
• Tropicos
• USDA PLANTS database
• VASCAN by Canadensys
• World Flora Online
• 日本のレッドデータ検索システム
• 植物和名−学名インデックス YList

iNat Map