Achillea millefolium, common yarrow
Aleksoff, Keith C. 1999. Achillea millefolium, common yarrow. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/achmil
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| ACHMIL | common yarrow | Achillea millefolium | Life Form: Plants/Forb Kingdom: Plantae Class: Dicot Order: Asterales Family: Asteraceae Genus: Achillea | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
Taxonomy
The scientific name of common yarrow is Achillea millefolium L. (Asteraceae) [26,36,44,73]. There are both native and introduced phases of common yarrow in North America. Introduced and native phases differ primarily in chromosome number and are difficult to distinguish morphologically [26,73]. Native and introduced phases hybridize. The intricate pattern of morphologic, geographic, and ecologic variation within the species has frustrated all efforts to organize an intraspecific taxonomy on a circumboreal or even a strictly North American basis [26]. Most authorities do not recognize infrataxa [26,73,74]; however, Kartesz [44] recognizes the following varieties:
- Achillea millefolium var. alpicola (Rydb.) Garrolt, common yarrow
- Achillea millefolium var. arenicola (Heller) Nobs, common yarrow
- Achillea millefolium var. borealis (Bong.) Farw., boreal yarrow
- Achillea millefolium var. californica (Pollard) Jepson, California yarrow
- Achillea millefolium var. gigantea (Pollard) Nobs, giant yarrow
- Achillea millefolium var. litoralis (Ehrend.) Nobs, coast yarrow
- Achillea millefolium var. megacephala (Raup) Bolvin, largehead yarrow
- Achillea millefolium var. occidentalis (DC.) Hyl., western yarrow
Synonyms
- Achillea lanulosa Nutt. [73]
Other Common Names
western yarrow, wooly yarrow
General Distribution
Common yarrow is circumboreal. In North America, it occurs in every state, province, and in Mexico [19,33]. It is adventitious in Hawaii [62].
States and Provinces
- United States: AL, AK, AZ, AR, CA, CO, CT, DE, FL, GA, HI, ID, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NM, NV, NH, NJ, NY, NC, ND, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VT, VA, WA, WV, WI, WY, DC, PR
- Canada: AB, BC, MB, NB, NF, NT, ON, PQ, SK, SK, YT
- Mexico
Site Characteristics
Common yarrow usually occupies dry, open sites in a variety of habitats across its range including sagebrush (Artemisia spp.)-grassland, canyon bottoms, glades, roadsides, and vacant lots. It is prevalent in brushlands, quaking aspen (Populus tremuloides), open timber, and subalpine zones. It is intolerant of dense shade. It is common on thin soils and sandy gravelly loam on open flats, parks, and dry meadows [69]. The elevational distribution in several western states is as follows [19]:
- Colorado: 4,000-12,000 feet (1220-3660 m)
- Montana: 2,400-10,000 feet ( 730-3050 m)
- Utah: 4,300-10,300 feet (1210-3040 m)
- Wyoming: 4,600-11,000 feet (1400-3350 m)
Plant Communities
Common yarrow occurs in a variety of plant communities across its wide distribution. It is not usually a community dominant [39,54].
Botanical Description
Common yarrow is a perennial forb 11 to 40 inches (30-100 cm) in height with extensive rhizomes. It has few to numerous erect stems. The basal rosette of leaves may remain green throughout the winter [43]. Plants grow in a somewhat scattered fashion and seldom form pure stands in areas larger than 5 square meters [69]. Typical European Achillea millefolium is hexaploid with flat leaves. Native forms are mostly tetraploid, with narrow leaf-segments disposed in various planes so that the leaf is 3-dimensional [33].
McLean [49] reported that in a Douglas-fir (Pseudotsuga menziesii) forest zone in British Columbia, the fibrous roots and rhizomes of yarrow grew mostly in the duff layer or between it and the mineral soil.
Raunkiaer Life Form (Raunkiaer 1934)
- Hemicryptophyte
Seasonal Development
Common yarrow has a long flowering season throughout its range, which varies as follows [19]:
| State | Earliest Month | Most Frequent Month | Latest Month |
|---|---|---|---|
| CO | May | May | June |
| ID | April | May | June |
| MT | May | May | June |
| UT | April | May | June |
| WY | May | June | August |
Average dates of different growth stages at different elevations in Utah were recorded as follows [22]:
| Elevation (feet) | Flower buds evident | Flowers in bloom | Seeds ripe | Seeds disseminated | Plant dried |
|---|---|---|---|---|---|
| 7,150 | 30 May | 29 June | 28 September | 19 September | 10 October |
| 7,655 | 01 June | 05 July | 26 August | 24 September | 13 October |
| 8,450 | 06 June | 10 July | 04 September | — | 25 September |
| 9,000 | 18 June | 15 July | 08 September | 29 September | 01 October |
| 10,100 | 25 June | 21 July | 20 September | 08 October | 08 October |
Average heights (cm) of plants at various dates and elevations from Ephraim Canyon in Utah were as follows (1925-1934) [22]:
| Elevation (feet) | 1 May | 15 May | 1 June | 15 June | 1 July | 15 July |
|---|---|---|---|---|---|---|
| 7,150 | 4.9 | 9.1 | 16.2 | 26.2 | 90.8 | 33.9 |
| 7,655 | 3.9 | 8.0 | 12.9 | 20.0 | 28.4 | 31.1 |
| 8,450 | 1.4 | 4.6 | 7.7 | 15.8 | 24.2 | 29.3 |
| 9,000 | — | 0.5 | 3.5 | 7.9 | 19.0 | 28.3 |
| 10,100 | — | — | — | 5.1 | 11.1 | 19.9 |
Over a 10-year period in Saskatchewan, Canada, flowering dates were recorded for yarrow [18]:
| Earliest flowering date | Latest flowering date | Mean flowering date | Latest date in flower | Mean flowering period |
|---|---|---|---|---|
28 May 1946 | 30 June 1950 | 19 June | 23 September | 78 days |
Regeneration Processes
Common yarrow regenerates from fragments of rhizomes and from colonization through short-distance (1-2 m) wind dispersal of seeds [15,47,61]. In disturbed soils, fragmented rhizomes regenerate shoots which can emerge from soil depths as great as 12 inches (30 cm). In undisturbed soil the rhizomes remain attached to the parent plant, forming new plants at the rhizome apices [15].
The fruit is a small achenes weighing about 0.17 mg. They are produced in large numbers. Several thousand achenes may be produced per flowering stem. The viability of freshly shed seeds exceeds 90%. Common yarrow seed showed 41% germination after 9 years in dry storage [15].
Successional Status
Common yarrow is a pioneer species everywhere it is found [1]. It is an invader species on disturbed rangeland sites. Common yarrow also appears to be tolerant of competition but not tolerant of excessive shade. It is usually present in the earliest stages of vegetation development and persists throughout succession [42]. It dominates on overgrazed high summer ranges, where the undisturbed climax vegetation would be made up of wheatgrasses (Triticeae) [69].
Immediate Fire Effects
Common yarrow's rhizomes and mycorrhizae are usually only slightly damaged by fire [10,38,60], although common yarrow is susceptible to fire-kill and reduction by severe fire [51].
Common yarrow is not highly flammable. Out of 14 species commonly found in boreal forests, common yarrow has the lowest potential ignitability based on chemical characteristics measured on live stem, live leaf and dead leaf tissues. These rankings rely primarily on total ash, silica-free ash and energy content [40]. Ignitability is measured as time to ignition.
Postfire Regeneration Strategy (Stickney 1989)
- Rhizomatous herb, rhizome in soil
- Initial-offsite colonizer (off-site, initial community)
Fire Adaptations
The life cycle of common yarrow in grasslands is completed by the onset of the summer drought and fire season in July [6]. Following fire, regeneration is from rapid rhizome spread [72] and wind dispersal of seeds onto burned sites from adjacent unburned areas [41].
Common yarrow occurs in plant communities with a variety of fire regimes. The range of fire intervals reported for some species that dominate communities where common yarrow occurs are listed below.
| Community dominant | Fire interval range (years) |
|---|---|
| Interior ponderosa pine (Pinus ponderosa var. scopulorum) | 20-42 |
| Rocky Mountain Douglas-fir (Pseudotsuga menziesii var glauca) | 10-30 |
| Quaking aspen (Populus tremuloides) | 7-10 |
| Rough fescue (Festuca altaica) | 5-10 |
Plant Response to Fire
Fire results in fragmentation of common yarrow's rhizomes stimulating regeneration [15]. Cover and frequency of common yarrow generally increase 1 to 2 years after fire but not with any consistent pattern [4,13,14,32,40,56,71]. After initially increasing in cover, common yarrow may decrease to unburned levels as early as 3 years after fire [17,37,65,75]. Production doubled within 3 to 4 years postfire near Missoula, Montana [6] and other ponderosa pine/mountain grassland ecosystems [32,69]. In another study of fire effects in ponderosa pine, common yarrow increased by 0.37 stem/m in 6 years, a negligible amount [55].
Common yarrow ground layer on the Stanislaus National Forest, 15 months after the 2013 Rim Fire.
Common yarrow is responsive to season of burning. Late spring burning usually reduces common yarrow [4,12,66].
Fire Regimes
For fire regime information, search FEIS for this species by entering the species name or acronym on the home page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
Common yarrow's good sprouting ability, high germination percentages, and competitive seedlings result in a remarkable persistence under fire disturbance. Common yarrow often appears in the first stages of succession [15,63]; however, no consistent trends relative to age of burns seem evident for the common yarrow [4,57].
Common yarrow has low ignitability, and can be used as a fire barrier, created by replacing highly flammable vegetation with species that are less likely to burn [41]. Planting less-flammable vegetation in fire-prone areas, or around property and fire-sensitive areas, may help prevent ignition or slow fire spread [40].
Fire Case Study Citation
Aleksoff, Keith C., compiler. 1999. Effects of a wildfire on common yarrow at White Cap Creek, Idaho. In: Achillea millefolium, common yarrow. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/achmil
Reference
Merrill, Evelyn H.; Mayland, Henry F.; Peek, James M. 1980. Effects of a fall wildfire on herbaceous vegetation on xeric sites in the Selway-Bitterroot Wilderness, Idaho. Journal of Range Management. 33(5): 363-367. [50].
Season/Severity Classification
Late summer/moderate
Study Location
The fire occurred in the Upper Selway River (White Cap Creek) drainage, Idaho. The area is a portion of a fire management zone in the Selway-Bitterroot Wilderness where fires are allowed to burn under natural conditions.
Prefire Vegetative Community
The fire occurred in a ponderosa pine (Pinus ponderosa) forest and adjacent montane grassland. Important understory species included common yarrow (Achillea millefolium), bluebunch wheatgrass (Pseudoroegneria spicata), arrowleaf balsamroot (Balsamorhiza sagittata), cheatgrass (Bromus tectorum), and prairie june grass (Koeleria macrantha).
Target Species Phenological State
Unknown, but most likely in flowering or seed ripening stage.
Site Description
- Aspect: south
- Elevation: 3,200-4,160 feet (1000-1300 m)
- Average annual precipitation: 760 mm, with peaks occurring from November to January and April to June
Soils are derived from Idaho batholith parent material consisting of decomposed granite, gneiss, and rhyolite. They are described as low in fertility, water-holding capacity, and of weak structure.
Fire Description
The fire occurred under extremely dry conditions, with relative humidity as low as 11%, maximum temperatures of 87 degrees Fahrenheit (32 °C), and winds gusting up to 27 miles/h (45 km/hr). The fire was a lightning-ignited and began 10 August, 1973, and burned for 43 days until extinguished by rain. The fire burned quickly and little ash was left.
Fire Effects on Target Species
Cover and frequency of common yarrow were equal to or lower than those on unburned sites during the 1st postfire year, but by the 3rd postfire year were greater than on unburned sites:
Postfire year | Burned | Unburned | Burned | Unburned |
|---|---|---|---|---|
| 1 | 2(2) | 2(2) | 5(4) | 5(2) |
| 3 | 12(12) | 4(5) | 11(5) | 6(12) |
Common yarrow plants on the burned sites grew to only 55% of the average height of plants on unburned sites in the 1st postfire year, but by the 2nd growing season were 51% taller than those on unburned sites. By the 3rd postfire year, heights on both sites were comparable.
Federal Status
None
Other Status
Boreal yarrow is state-listed as a species of special concern in Maine [48].
Importance to Wildlife and Livestock
Common yarrow varies greatly in forage value, depending on locality and seasonal development. It is generally unpalatable, although domestic livestock and wildlife occasionally consume the flowers. Cattle and horses usually do not graze common yarrow, but bighorn sheep, pronghorn, and deer may use it. They most often graze the flowerheads. common yarrow provides fair forage for domestic sheep and goats [24,43]. The average summer use is 20% for cattle and horses and 40% for domestic sheep and goats [58]. Common yarrow is an important food of 4- to 8-week-old sage grouse chicks [16].
Common yarrow contains volatile oils, alkaloids, and glycosides but is not generally considered a toxic plant because it is so seldom consumed by livestock. Milk from cows consuming common yarrow has a "disagreeable" flavor [64].
Palatability and Nutritional Value
The palatability of common yarrow to livestock and wildlife in several western states has been rated as follows [27]:
| Animal | CO | MT | ND | UT | WY |
|---|---|---|---|---|---|
| Cattle | poor | poor | poor | poor | poor |
| Domestic sheep | fair | fair | fair | good | fair |
| Horses | poor | poor | poor | poor | poor |
| Pronghorn | — | poor | fair | fair | fair |
| Elk | — | poor | — | fair | fair |
| Mule deer | — | poor | fair | fair | fair |
| White-tailed deer | — | poor | poor | — | fair |
| Small mammals | — | poor | — | fair | fair |
| Small nongame birds | — | poor | — | fair | poor |
| Upland game birds | — | poor | — | fair | good |
| Waterfowl | — | — | — | poor | poor |
Common yarrow is rated as poor in energy and protein content [27]. In Northern Utah, plants growing on unfavorable sites (defined by slope, exposure, and vegetation cover) were 9% higher in crude protein than plants growing on favorable sites [21]. ,Monthly nutrient values and moisture content of common yarrow collected from Cold Meadows in the River of No Return Wilderness, Idaho, (1977 to 1978) were as follows [29]:
| Nutrient | June | July | August |
|---|---|---|---|
| Crude fiber | 22(2.0) | 24(1.8) | 25(1.2) |
| Crude protein | 20(1.6) | 17(0.3) | 14(0.9) |
| Moisture | 78(5) | 64(2) | 58(3) |
| Ca:P | 2.7:1 | 4.5:1 | 5.1:1 |
Cover Value
The degree to which yarrow provides cover for wildlife has been rated as follows [27]:
| Animal | CO | MT | ND | UT | WY |
|---|---|---|---|---|---|
| Pronghorn | — | — | fair | poor | poor |
| Elk | — | — | — | poor | poor |
| Mule deer | — | — | fair | poor | poor |
| Small mammals | good | poor | — | fair | poor |
| Small nongame birds | good | poor | fair | fair | poor |
| Upland game birds | — | poor | — | fair | poor |
| Waterfowl | — | — | — | poor | poor |
| White-tailed deer | — | — | fair | — | poor |
Value for Rehabilitation or Restoration of Disturbed Sites
Due to its extensive system of rhizomes, common yarrow is a good soil binder [59] and has been used in erosion control projects on the Wasatch Plateau in central Utah [69]. In Massachusetts, seed-grown sod of common yarrow, along with sod of 11 other species, was transplanted onto a roadside site with shallow, infertile soil and direct exposure. After 4 years, common yarrow was one of 3 surviving species on the site [2].
Other Uses
Native Americans used tea made from common yarrow to relieve ear-, tooth-, and headaches; as an eyewash; to reduce swelling; and as a tonic or stimulant. common yarrow varies in taste and in potency depending on where it grows and at what stage of growth it is in. The best time to collect yarrow for tea is right before the flowers are produced, using only the new succulent leaves [34]. During the Civil War, common yarrow was widely used to treat wounds and became known as "soldiers' woundwort." An ethanol extract of common yarrow has mosquito- repelling properties [67].
Common yarrow is used for summer and winter bouquets. When cut fresh and kept in water, common yarrow flavors the air with an aromatic spiciness [43,64].
Other Management Considerations
Common yarrow tends to increase rapidly in disturbed areas or overgrazed rangelands, replacing more valuable forage species and crops [43]. It is often an indicator of past overstocking and excessive utilization [69]. Common yarrow tends to decrease on grazing plots once grazing has ceased [7,20]. Since rhizomes are a major means of common yarrow regeneration, starting control measures early in autumn may prevent spring growth from autumn and winter rhizome dry matter [15]. In New Zealand, barley (Hordeum vulgare) reduced rhizome and seed production in common yarrow [15].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- FRES17 Elm-ash-cottonwood
- FRES20 Douglas-fir
- FRES21 Ponderosa pine
- FRES23 Fir-spruce
- FRES29 Sagebrush
- FRES30 Desert shrub
- FRES34 Chaparral-mountain shrub
- FRES35 Pinyon-juniper
- FRES36 Mountain grasslands
- FRES38 Plains grasslands
- FRES39 Prairie
- FRES41 Wet grasslands
- FRES44 Alpine
BLM Physiographic Regions (Bernard and Brown 1977)
- 1 Northern Pacific Border
- 2 Cascade Mountains
- 3 Southern Pacific Border
- 4 Sierra Mountains
- 5 Columbia Plateau
- 6 Upper Basin and Range
- 7 Lower Basin and Range
- 8 Northern Rocky Mountains
- 9 Middle Rocky Mountains
- 10 Wyoming Basin
- 11 Southern Rocky Mountains
- 12 Colorado Plateau
- 13 Rocky Mountain Piedmont
- 14 Great Plains
- 15 Black Hills Uplift
- 16 Upper Missouri Basin and Broken Lands
Kuchler Plant Associations (Kuchler 1964)
- K011 Western ponderosa forest
- K012 Douglas-fir forest
- K015 Western spruce-fir forest
- K016 Eastern ponderosa forest
- K018 Pine-Douglas-fir forest
- K019 Arizona pine forest
- K021 Southwestern spruce-fir forest
- K023 Juniper-pinyon woodland
- K037 Mountain mahogany-oak scrub
- K038 Great Basin sagebrush
- K040 Saltbush-greasewood
- K049 Tule marshes
- K051 Wheatgrass-bluegrass
- K052 Alpine meadows and barren
- K055 Sagebrush steppe
- K056 Wheatgrass-needlegrass shrubsteppe
- K063 Foothills prairie
- K064 Grama-needlegrass-wheatgrass
- K065 Grama-buffalograss
- K066 Wheatgrass-needlegrass
- K067 Wheatgrass-bluestem-needlegrass
- K070 Sandsage-bluestem prairie
- K074 Bluestem prairie
- K098 Northern floodplain forest
SAF Cover Types (Eyre 1980)
- 210 Interior Douglas-fir forest
- 216 Blue spruce
- 217 Aspen
- 218 Lodgepole pine
- 219 Limber pine
- 237 Interior ponderosa pine
SRM Rangeland Cover Types (Shiflet 1994)
- 101 Bluebunch Wheatgrass
- 102 Idaho Fescue
- 103 Green Fescue
- 104 Antelope Bitterbrush-Bluegrass Wheatgrass
- 105 Antelope Bitterbrush-Idaho Fescue
- 107 Western Juniper-Big Sagebrush
- 109 Ponderosa pine shrubland
- 110 Ponderosa Pine-Grassland
- 204 North Coastal Shrub
- 309 Idaho Fescue-Western Wheatgrass
- 315 Big Sagebrush-Idaho Fescue
- 316 Big Sagebrush-Rough Fescue
- 317 Bitterbrush-Bluebunch Wheatgrass
- 323 Shrubby Cinquefoil-Rough Fescue
- 401 Basin Big Sagebrush
- 402 Mountain Big Sagebrush
- 409 Tall Forb
- 411 Aspen Woodland
- 413 Gambel Oak
- 608 Wheatgrass-Grama-Needlegrass
- 610 Wheatgrass
- 613 Fescue Grassland
- 805 Riparian
- 910 Hairgrass
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