Achillea millefolium L.
yarrow (common yarrow)
Asteraceae (Aster family)

Introduction to Vascular Plants


© Dave Purdy     (Photo ID #83926)


E-Flora BC Static Map

Distribution of Achillea millefolium
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Species Information

Perennial, aromatic herb, usually rhizomatous; stems erect, slender, 10-100 cm tall.
Fernlike, alternate, stalked below and unstalked above, pinnately dissected, the divisions again dissected.
Heads numerous, in a short, flat or round-topped cluster; involucral bracts dry, overlapping in several series, often dark-margined; ray flowers usually 3-8, 2-3.5 mm long, white to sometimes pink or reddish; disk flowers 15-40, cream colored.
Achenes glabrous, flattened, 1-2 mm long; pappus lacking.
Taxonomically, one of our most complex species. Tyrl (1980) presented a sound case for recognizing only a single variable species. I, however, have recognized four, broad ecogeographical forms (sensu Nobs 1960) at the varietal level since these forms are ecologically significant in BC.

1. Leaves grey, long-hairy to woolly; plants usually in and east of the Coast-Cascade Mountains.

2. Involucral bract margins light brown to black; stems usually less than 30 cm tall; plants of the subalpine and alpine zones................. var. alpicola (Rydb.) Garrett

2. Involucral bract margins light brown to straw-coloured; stems usually more than 30 cm tall; plants of the montane and steppe zones........................ var. lanulosa (Nutt.) Piper in Piper & Beattie

1. Leaves usually green, moderately long-hairy; plants of coastal regions.

3. Involucral bract margins dark brown to black; stems 10-40 cm tall........................ var. borealis (Bong.) Farwell

3. Involucral bract margins hyaline to light straw-coloured; stems 30-100 cm tall.................. var. pacifica (Rydb.) G.N. Jones

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

USDA Species Characteristics

Flower Colour:
Blooming Period:
Early Summer
Fruit/Seed characteristics:
Colour: Brown
Present over the Summer
Source:  The USDA


Ecological Framework for Achillea millefolium

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
1143 0 2854
Slope Gradient (%)
24 0 360

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

189 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
3 0 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

AT(124), BAFA(34), BG(471), BWBS(468), CDF(63), CMA(4), CWH(110), ESSF(1352), ICH(346), IDF(2274), IMA(24), MH(18), MS(822), PP(577), SBPS(448), SBS(848), SWB(178)

Habitat and Range

Mesic to dry coastal bluffs, meadows, grasslands, rocky slopes and open forests in all vegetation zones; common throughout BC; N to AK, YT and NT, E to NF and S to FL, TX, CA, and MX. Description

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Achillea magna auct.

Taxonomic Notes

This species has been observed flowering in the Fraser Delta in December.