[Yarrows: The Genus Achillea East of the Cascade Mts. of Oregon and Washington]
Common Yarrow, Yarrow, Milfoil, Achillee millefeuille, Herbe-a-dinde
Achillea millefolium
Synonyms: Achillea alpicola, Achillea arenicola, Achillea borealis, Achillea borealis ssp. arenicola, Achillea borealis ssp. californica, Achillea californica, Achillea gigantea, Achillea lanulosa, Achillea lanulosa sp. alpicola, Achillea lanulosa var. eradiata, Achillea lanulosa var. lanulosa, Achillea laxiflora, Achillea megacephala, Achillea millefolium ssp. borealis, Achillea millefolium ssp. lanulosa, Achillea millefolium var. alpicola, Achillea millefolium var. arenicola, Achillea millefolium var. asplenifolia, Achillea millefolium var. borealis, Achillea millefolium var. californica, Achillea millefolium var. gigantea, Achillea millefolium var. lanulosa, Achillea millefolium var. litoralis, Achillea millefolium var. maritima, Achillea millefolium var. megacephala, Achillea millefolium var. millefolium, Achillea millefolium var. nigrescens, Achillea millefolium var. occidentalis, Achillea millefolium var. pacifica, Achillea millefolium var. puberula, Achillea nigrescens, Achillea occidentalis, Achillea pacifica, Achillea puberula, Achillea rosea, Achillea subalpina
The photo above shows a close-up of the inflorescence of yarrow as seen on Missoula Flood sandbars between Five Mile and the Little Spokane River, Spokane County, WA.......June 29, 2018. Note the 3-5 ray flowers and several white disk flowers that makes up each tiny flower head.
Characteristics:
Yarrow is perhaps the most numerous plant in the inland Pacific Northwest.
It is a native, but can sometimes be very weed-like It is an upright perennial
with one main stem and occasional branching. The stems arise 3-30 cm tall. The
herbage is smooth to pubescent. The basal and stem leaves are pinnately dissected,
with only the lower ones petioled. The leaves alternate along the stem and are
up to 15 cm long.
The inflorescence is a flat-topped corymb consisting of numerous small flower
heads consisting of 3-5 white rays surrounding a tiny disk of 10-30 white flowers.
The rays are 2-3 mm long.
Habitat:
Yarrow is found in multiple habitats, from alpine to forest, to roadside and
plains.
Range:
Yarrow is found over much of the northern hemisphere. On the east coast of
North America, it is most likely an import from Europe.
Importance/ Uses:
Achillein, a blood clotting extract from yarrow is used by pharmacists today
to reduce clotting time. A tea may be made from the flowers, leaves, and stems
to help regulate digestion and reduce lethargy. The plant is a great one for
dried wintertime flora arrangements. Early in the growing season, the plant
is more succulent and may thus be browsed by sheep, deer, and pronghorn. Sage
grouse also may feed off of the plant.
Historically, the Nez Perce ground the dried plants into flour and used the
leaves to stop bleeding. They use the leaves as a tea to reduce fevers.
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Yarrow as seen at the East Rim Viewpoint, Steens Mountain.........July 11, 2014.
Yarrow blooming at about 9400' at the head of the Little Blitzen Gorge, Steens Mountain, Harney County, Oregon........September 1, 2011.
Yarrow as seen along FS Road 38-200 near Spanish Peak, Ochoco National Forest..........June 14, 2015.
The photos above and below of yarrow (variety occidentalis) were taken along forest road #23 at the Mt. Adams Viewpoint at about 3800' at the southwestern corner of Mt. Adams........October 14, 2005.
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Yarrow still blooming along the South Loop Road(left) about one mile downhill to the west of the East Rim Viewpoint, Steens Mountain..........September 20, 2015. The photo at right shows a blooming inflorescence of yarrow on the west rim of Kiger Gorge, Steens Mountain..........September 19, 2015..
The photo above shows a close-up dorsal-view of the inflorescence of yarrow (variety occidentalis) as seen at about 2700' along road K6000 at the southeastern corner of Mt. Adams.......July 11, 2005. Note the 3-5 ray flowers and several white disk flowers that makes up each tiny flower head.
Close-up of the inflorescence of yarrow as seen at the Steens Mountain Summit, southeastern Oregon........September 1, 2011.
Paul Slichter