Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide


Artemisia biennis
(biennial wormwood)



Artemisia biennis (biennial wormwood)


  • Last modified
  • 14 November 2018
  • Datasheet Type(s)
  • Invasive Species
  • Preferred Scientific Name
  • Artemisia biennis
  • Preferred Common Name
  • biennial wormwood
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Spermatophyta
  •       Subphylum: Angiospermae
  •         Class: Dicotyledonae
  • Summary of Invasiveness
  • The large seed production, small sticky seeds and adaptation to disturbed habitats facilitated the early and rapid spread of A. biennis beyond its natural range in North America, along transportation corridor...

  • There are no pictures available for this datasheet

    If you can supply pictures for this datasheet please contact:

    CAB International
    OX10 8DE
  • Distribution map More information

Don't need the entire report?

Generate a print friendly version containing only the sections you need.

Generate report


Top of page

Preferred Scientific Name

  • Artemisia biennis Willd.

Preferred Common Name

  • biennial wormwood

Other Scientific Names

  • Artemisia australis Ehrh. ex DC.
  • Artemisia biennis var. biennis
  • Artemisia biennis var. diffusa Dorn
  • Artemisia canescens Willd.
  • Artemisia cernua Dufour ex Willk. & Lange
  • Artemisia cernuiflora Dufour ex Willk. & Lange
  • Artemisia eschscholtziana Besser
  • Artemisia inconspicua Spreng.
  • Artemisia jacquinii Raeusch.
  • Artemisia microcephala Hillebr.
  • Artemisia pyromacha Viv.
  • Artemisia ramosa Lag. ex Willk. & Lange
  • Artemisia seriphium Pourr. ex Willk. & Lange

International Common Names

  • English: biennial sagewort; false tansy; slender mugwort
  • French: armoise bisannuelle; herbe St-Jean

Local Common Names

  • Germany: Zweijähriger Beifuß
  • Netherlands: rechte alsem; tweejarige alsem

Summary of Invasiveness

Top of page

The large seed production, small sticky seeds and adaptation to disturbed habitats facilitated the early and rapid spread of A. biennis beyond its natural range in North America, along transportation corridors and in association with human activities. In recent decades it has become invasive in some agricultural areas in North America. The increasing prevalence of A. biennis in agricultural lands seems to be associated with several factors, including: a shift to annual growth habit; increasing adoption of reduced tillage systems; crop diversification; and, a tolerance to several classes of herbicides. In Europe, the plant has become a local weed, but has not yet been reported as invasive in crops. However, increased frequency has been observed in some countries and changes in land use and agricultural practices suggest the potential for emerging problems in Europe in the future.

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Dicotyledonae
  •                     Order: Asterales
  •                         Family: Asteraceae
  •                             Genus: Artemisia
  •                                 Species: Artemisia biennis

Notes on Taxonomy and Nomenclature

Top of page

The genus Artemisia is a highly diverse and taxonomically complicated genus with about 500 species worldwide (Schultz, 2006). Infrageneric classification puts A. biennis in the subgenus Artemisia, which is characterized by heterogamous flower heads with female outer florets, bisexual and fertile central florets, and a glabrous receptacle (Vallès and McArthur, 2001; Pellicer et al., 2010). A. biennis is closely related to the Eurasian species A. tournefortiana and the two species are sometimes grouped together as conspecific. A. magellanica is also closely related and is too sometimes grouped with A. biennis. For example, Ling (1995) included both A. tournefortiana and A. magellanica, as well as other taxa, within his broad concept of A. biennis. The various species concepts to which the name has been applied in the literature can be confusing and caution is needed when interpreting its use.

One unusual variation with atypically short leaves and many short branches originating from the base of the main stem, A. biennis var. diffusa (Dorn, 1988), is usually treated as a minor variant of no taxonomic significance (Ling, 1995; Schultz, 2006).


Top of page

A. biennis is an annual or biennial herbaceous plant. Stems are 1–3 m tall (although flowering plants may be as little as a few cm tall), erect and more or less spike-like, simple or somewhat branching at the base from a firm taproot. The stems are glabrous throughout, striate and often reddish.The leaves are alternate, glabrous, sessile, pinnatifid into narrow lobes with the lower leaf segments also pinnatifid, lobes of all but the uppermost toothed. Inflorescence a compound spike-like panicle, leafy throughout, with dense clusters of more or less globose capitula (flower heads) which are nearly sessile along short branches arising from upper leaf axils. Each flower head consists of a hemispheric involucre 2–3 cm long, made of 8–14 glabrous bracts. There are 6–22 or more outer pistillate (ray) florets, and 15–40 central bisexual disc florets. Corollas very small, pale yellow to whitish, with scattered stalked glands; corollas of the outer ray flowers about 1 mm long, somewhat tubular; those of the disk flowers bell-shaped, 1–2 mm long, with five triangular teeth. Cypselae (seeds) obovoid to ellipsoid, glabrous, lacking a pappus (bristles), very small (0.2–0.9 mm long), longitudinally 4-5 nerved and light brown.


Top of page

The precise native range of A. biennis is not known, but has been assumed to be the northwestern USA and adjacent areas of southwestern Canada (Thomas, 1961; Cronquist, 1994).

Records of A. biennis in Argentina, Brazil and Russia (Ling, 1995) are thought to be invalid. In addition to this, records in Iran (Nematollahi et al., 2006), India (Sood et al., 2001) and China (Lin et al., 2011) are thought to represent A. tournefortiana.

Distribution Table

Top of page

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes


ChinaPresentLin et al., 2011Record thought to represent A. tournefortiana
IndiaPresentSood et al., 2001Record thought to represent A. tournefortiana
IranPresentNematollahi et al., 2006Record thought to represent A. tournefortiana

North America

CanadaPresentPresent based on regional distribution.
-AlbertaPresentNative Invasive Kegode and Darbyshire, 2013; USDA-ARS, 2015
-British ColumbiaPresentGroh, 1944; Douglas et al, 1998; USDA-ARS, 2015Recorded as both introduced and native species
-ManitobaLocalisedIntroduced Invasive Gulden, 2009; Kegode and Darbyshire, 2013
-New BrunswickPresentIntroduced Not invasive Groh, 1944; Kegode and Darbyshire, 2013Introduced in 1879
-Northwest TerritoriesPresentIntroduced Not invasive Kegode and Darbyshire, 2013; USDA-ARS, 2015
-Nova ScotiaPresentIntroduced Not invasive Kegode and Darbyshire, 2013
-OntarioPresentIntroducedGroh, 1944; Kegode and Darbyshire, 2013Some disagreement between sources whether invasive. Introduced in 1879
-Prince Edward IslandLocalisedIntroduced1912 Not invasive Erskine, 1961
-QuebecPresentIntroducedRousseau, 1968; Kegode and Darbyshire, 2013Introduced in 1864. Some disagreement between sources as to whether invasive
-SaskatchewanWidespreadNative Invasive Kegode and Darbyshire, 2013
-Yukon TerritoryPresentIntroduced Not invasive Kegode and Darbyshire, 2013; USDA-ARS, 2015
USAPresentPresent based on regional distribution.
-AlaskaPresentIntroducedKegode and Darbyshire, 2013; USDA-ARS, 2015
-ArizonaPresentNativeUSDA-ARS, 2015
-CaliforniaPresentNativeUSDA-ARS, 2015
-ColoradoPresentNativeUSDA-ARS, 2015
-DelawarePresentIntroducedUSDA-ARS, 2015
-District of ColumbiaPresentIntroducedKartesz, 2014
-IdahoPresentNativeUSDA-ARS, 2015
-IllinoisPresentIntroduced Invasive Johnson et al., 2004; USDA-ARS, 2015
-IndianaPresentIntroduced Invasive Johnson et al., 2004; USDA-ARS, 2015
-IowaPresentIntroduced Invasive Johnson et al., 2004; USDA-ARS, 2015
-KansasPresentIntroducedUSDA-ARS, 2015
-KentuckyPresentIntroducedUSDA-ARS, 2015
-LouisianaPresentIntroducedKartesz, 2014
-MainePresentIntroducedUSDA-ARS, 2015
-MarylandPresentIntroducedUSDA-ARS, 2015
-MassachusettsPresentIntroducedUSDA-ARS, 2015
-MichiganPresentIntroduced Invasive Johnson et al., 2004; USDA-ARS, 2015
-MinnesotaPresentIntroduced Invasive Johnson et al., 2004; Kegode and Darbyshire, 2013; USDA-ARS, 2015
-MissouriPresentIntroducedUSDA-ARS, 2015
-MontanaPresentNativeUSDA-ARS, 2015
-NebraskaPresentIntroducedUSDA-ARS, 2015
-NevadaPresentNativeUSDA-ARS, 2015
-New HampshirePresentIntroducedUSDA-ARS, 2015
-New JerseyPresentIntroducedUSDA-ARS, 2015
-New MexicoPresentNativeUSDA-ARS, 2015
-New YorkPresentIntroducedUSDA-ARS, 2015
-North DakotaPresentKegode and Fronning, 2005; USDA-ARS, 2015Some disagreement between sources as whether introduced or native
-OhioPresentIntroducedUSDA-ARS, 2015
-OregonPresentNativeUSDA-ARS, 2015
-PennsylvaniaPresentIntroducedUSDA-ARS, 2015
-Rhode IslandPresentIntroducedUSDA-ARS, 2015
-South CarolinaPresentIntroducedKartesz, 2014
-South DakotaPresentIntroduced Invasive Kegode and Christoffers, 2003; USDA-ARS, 2015
-TennesseePresentIntroducedKartesz, 2014
-UtahPresentNativeUSDA-ARS, 2015
-VermontPresentIntroducedUSDA-ARS, 2015
-WashingtonPresentNativeUSDA-ARS, 2015
-West VirginiaPresentIntroducedKartesz, 2014
-WisconsinPresentIntroduced Invasive Johnson et al., 2004; USDA-ARS, 2015
-WyomingPresentNativeUSDA-ARS, 2015

South America

ArgentinaPresentLing, 1995Record thought to be invalid
BrazilPresentLing, 1995Record thought to be invalid


BelgiumPresentIntroducedEuro+Med PlantBase, 2011
Czech RepublicPresentDatamining 2011 - Invasive Species Databases
Czechoslovakia (former)PresentIntroducedEuro+Med PlantBase, 2011
DenmarkPresentIntroducedHegi, 1929; Jehlík, 1984; Euro+Med PlantBase, 2011Introduced before 1929
FinlandPresentIntroducedEuro+Med PlantBase, 2011
FranceLocalisedIntroducedEuro+Med PlantBase, 2011Introduced post 1945
GermanyPresentIntroduced1890sHegi, 1929; Euro+Med PlantBase, 2011
IrelandPresentIntroducedEuro+Med PlantBase, 2011
ItalyPresentIntroducedEuro+Med PlantBase, 2011
LuxembourgPresentIntroducedEuro+Med PlantBase, 2011
NetherlandsPresentIntroducedHegi, 1929; Euro+Med PlantBase, 2011; Meisner et al., 2011
NorwayPresentIntroduced1925Jehlík, 1984; Euro+Med PlantBase, 2011
PolandPresentIntroduced1938Jehlík, 1984; Euro+Med PlantBase, 2011
Russian FederationPresentLing, 1995Record thought to be invalid
SwedenPresentIntroducedHegi, 1929; Jehlík, 1984Introduced before 1929
SwitzerlandPresentIntroduced1917Hegi, 1929; Gut and Weber, 1999
UKLocalisedIntroducedStace, 1997

History of Introduction and Spread

Top of page

Historical records suggest that the species has moved north, south and eastwards across the North American continent with the aid of human activity. Gray (1848) reported A. biennis occurring on river banks from Ohio westwards, indicating that it had already spread through much of the northwestern states by the mid 1800s. By the time of his fifth edition, Gray (1867) noted that the species was moving eastward with the railways and a century later, it was reported as present throughout the northeastern states and in much of eastern Canada (Fernald, 1950). In western Canada it was first reported from northern Saskatchewan and the Northwest Territories in the 1820s (Drummond, 1830; Hooker, 1840), where it may have been native or introduced along early trading routes. By the end of the century, it was recognized as a weed in grain and hayfields of the Great Plains (Fletcher, 1897) and had spread into eastern Canada (Macoun, 1883; Rousseau, 1968).

Introduction of A. biennis into Europe appears to have been accidental, as a contaminant in grain, oilseeds or other factory raw materials. Hegi (1929) stated that the species reached parts of Germany and adjacent countries in the late nineteenth and early twentieth centuries. The species reached other parts of Europe as an introduced casual, occasionally becoming naturalized in some areas as recently as after the Second World War. 


Top of page
Introduced toIntroduced fromYearReasonIntroduced byEstablished in wild throughReferencesNotes
Natural reproductionContinuous restocking
Czechoslovakia (former) Canada 1960 Yes No Jehlík (1984) Seeds rarely ripen
Finland Canada 1925 No No Suominen (1979) Introduced in grain imports
Germany Canada 1894-1914 Yes No Hegi (1929) Introduced as a result of oilseeds and factory mills
UK Canada 1911 No No Stace (1997) Introduced in grain and wool imports

Risk of Introduction

Top of page

As A. biennis becomes more common in North American agricultural crops, the risk of it spreading as a commodity contaminant or hitchhiker increases correspondingly. The production of a large number of tiny seeds which are difficult to detect can enter the trade of transported goods in various ways. Although the small seeds are easy to remove with commodity cleaning techniques when dry, if A. biennis seeds come into contact with moisture, an outer pertinacious slime layer is produced making them sticky even when subsequently dried out (Kreitschitz, 2012).


Top of page

 In some areas A. biennis can completely dominate disturbed habitats, such as fallow fields (Hall and Clements, 1923). A. biennis is associated with early successional habitats with other pioneer plant species.

A. biennis is a species of grasslands, meadows, roadsides, waste places and fallow agricultural fields, as well as crop fields. In non-agricultural situations A. biennis occurs in a wide range of habitats, often characterized by natural or anthropogenic disturbances, including, shores, riparian habitats, salt marshes, mud flats, gravel bars, sloughs, talus slopes, ditches, gardens, roadsides, railway embankments, quarries, field edges and burnt-over areas.

Habitat List

Top of page
Terrestrial – ManagedCultivated / agricultural land Principal habitat Harmful (pest or invasive)
Cultivated / agricultural land Principal habitat Productive/non-natural
Disturbed areas Principal habitat Harmful (pest or invasive)
Disturbed areas Principal habitat Natural
Rail / roadsides Principal habitat Harmful (pest or invasive)
Rail / roadsides Principal habitat Natural
Urban / peri-urban areas Present, no further details
Terrestrial ‑ Natural / Semi-naturalRiverbanks Principal habitat Harmful (pest or invasive)
Riverbanks Principal habitat Natural
Wetlands Secondary/tolerated habitat Harmful (pest or invasive)
Wetlands Secondary/tolerated habitat Natural
Rocky areas / lava flows Principal habitat Harmful (pest or invasive)
Rocky areas / lava flows Principal habitat Natural
Scrub / shrublands Secondary/tolerated habitat Harmful (pest or invasive)
Scrub / shrublands Secondary/tolerated habitat Natural
Coastal areas Present, no further details

Biology and Ecology

Top of page


Chromosome counts ofn = 9, 2n = 18 have been reported (Powell et al., 1974; Löve and Löve, 1982). Relatively high levels of genetic diversity were found in A. biennis populations in Minnesota and North and South Dakota, USA. This diversity is attributed in part to low levels of genetic exchange amongst populations (Mengistu et al., 2004).

Reproductive Biology

Species in the genus Artemisia are primarily wind pollinated, but may be visited occasionally by pollen eating insects (Knuth, 1908). Cross pollination is inferred to be the rule (Kegode and Christoffers, 2003); but self pollination may occur (Mulligan and Findlay, 1970). Reproduction is solely by prolific seed production with up to a million seeds produced per plant (Stevens, 1932; Mahoney and Kegode, 2004).

Physiology and Phenology

Annual forms will emerge throughout the growing season when conditions are favourable (Mahoney and Kegode, 2004). In North America seedlings tend to emerge from light soils earlier (May) than from heavy soils (late-June), while 70% of emergence occurs in July in all soils (Fronning and Kegode, 2004a, 2004b; Kegode et al., 2007). Mahoney and Kegode (2004) reported seedlings that emerged and had five weeks of growth at a juvenile stage produced seed, whereas seedlings with a shorter juvenile stage did not produce seed or survive the winter. Late emergence can allow seedlings to escape herbicide control (Kegode and Fronning, 2005). Biennial forms develop very slowly in the first year, with growth concentrated in the root and rosette leaves, ensuring sufficient storage capacity for successful overwintering. New growth from the roots in early spring ensures rapid vegetative growth and full flowering and seed production in the second year. Plants compete with crop species for light and can reach the adult stage by the end of the season, producing less biomass in the roots and first leaves and more in the development of the stem and reproductive parts (Mahoney and Kegode, 2004).

Allelopathic effects have been observed in this species, with increasing effect as plants increase in size (Kegode and Ciernia, 2005).


A. biennis is an annual or biennial herbaceous plant.

Environmental Requirements

A. biennis is highly adaptable to a range of soils and microclimates in temperate, continental climate zones, provided that adequate moisture is available. The species is photoperiod sensitive, with the result that if day lengths are not optimal at flowering time, plants may either produce a much lower number of seeds than usual, or fail to develop seeds altogether (Jehlik, 1984; Mahoney and Kegode, 2004). Plants, particularly the annual form, are unlikely to survive early frost or cold winters.


Top of page
BS - Steppe climate Preferred > 430mm and < 860mm annual precipitation
Cs - Warm temperate climate with dry summer Preferred Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers
Ds - Continental climate with dry summer Preferred Continental climate with dry summer (Warm average temp. > 10°C, coldest month < 0°C, dry summers)

Latitude/Altitude Ranges

Top of page
Latitude North (°N)Latitude South (°S)Altitude Lower (m)Altitude Upper (m)
60 33

Notes on Natural Enemies

Top of page

Very little is known about herbivores attacking A. biennis. A number of fungi were reported on A. biennis in North America, including: Albugo tragopogonis [Pustula tragopogonis], Leptosphaeria pyrenopezizoides, Ophiobolus claviger, O. fulgidus, O. tanaceti, Peronospora artemisiae-biennis [Paraperonospora artemisiae-biennis], P. leptosperma [Paraperonospora leptosperma], Puccinia atrofusca, P. universalis and Thanatephorus cucumeris (Farlow, 1884; Brenckle, 1917, 1918; Bisby et al., 1938; Shoemaker, 1976; Frank, 1981; Kegode and Darbyshire, 2013).

Means of Movement and Dispersal

Top of page

Natural Dispersal

Although the production of sticky slime may assist dispersal under some conditions, this is likely only a secondary factor in seed dispersal (Kegode and Darbyshire, 2013). Natural vectors may include water, wind and animals.

Vector Transmission

Animals may assist in dispersal of seeds, either by seed caching or the adherence of sticky seed to body parts. When A. biennis seed comes into contact with moisture an outer pertinacious slime layer is produced making them sticky even when subsequently dried out (Kreitschitz, 2012).

Accidental Introduction

Introduction of A. biennis into Europe appears to have been accidental, as a contaminant in grain, oilseeds or other factory raw materials. The small size and potential stickiness of seeds contribute to the likelihood of contamination of traded goods and packing.

Impact Summary

Top of page
Economic/livelihood Negative
Human health Negative

Economic Impact

Top of page

The economic impact of A. biennis is largely due to the yield loss and weed management associated with agricultural crops which it infests. Stevens (1950) suggested that as a biennial species, A. biennis would be largely controlled in agricultural fields by annual cultivation, however, a shift to annual growth habit is now seen in most agricultural ecosystems (Kegode and Darbyshire, 2013). Increased occurrence of A. biennis in cropping systems appears to be related to a combination of factors that include selection of annual forms (Kegode and Christoffers, 2003) and increased practice of conservation tillage (Blackshaw et al., 2006). In addition, A. biennis is a significant weed in some regions of North America due to factors, which include, increasing bean acreage, misidentification as common ragweed, limited herbicide options providing control, and extended seedling emergence period (Kegode and Christoffers, 2003).

Environmental Impact

Top of page

Impact on Biodiversity

A. biennis is alleopathic and will inhibit the growth of other plants. This enables it to outcompete native species reducing biodiversity.

Threatened Species

Top of page
Threatened SpeciesConservation StatusWhere ThreatenedMechanismReferencesNotes
Centrocercus minimus (Gunnison sage-grouse)USA ESA listing as threatened species USA ESA listing as threatened speciesColorado; UtahEcosystem change / habitat alterationUS Fish and Wildlife Service, 2013

Social Impact

Top of page

As a plant which causes hay fever, social impact occurs when human health is affected by airborne pollen. However, A. biennis is usually not the most problematical species contributing allergenic pollen to the air but may contribute to asthma.

Risk and Impact Factors

Top of page Invasiveness
  • Invasive in its native range
  • Proved invasive outside its native range
  • Abundant in its native range
  • Highly adaptable to different environments
  • Is a habitat generalist
  • Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
  • Pioneering in disturbed areas
  • Benefits from human association (i.e. it is a human commensal)
  • Fast growing
  • Has propagules that can remain viable for more than one year
Impact outcomes
  • Ecosystem change/ habitat alteration
  • Negatively impacts agriculture
  • Negatively impacts human health
  • Damages animal/plant products
Impact mechanisms
  • Allelopathic
  • Competition - monopolizing resources
  • Competition - shading
Likelihood of entry/control
  • Highly likely to be transported internationally accidentally
  • Difficult/costly to control


Top of page

Social Benefit

Essential oils in A. biennis have both antibacterial and antifungal properties and have been used in traditional medicines in North America (Lopez-Lutz et al., 2008).

Similarities to Other Species/Conditions

Top of page

The glabrous foliage and annual/biennial growth habit distinguishes A. biennis from other similar and common weeds such as common ragweed (Ambrosia artemisiifolia), common wormwood (Artemisia absinthium) and many other Artemisia species. It particularly resembles the annual weedy species Artemisia annua, but the leaves of this species are more finely dissected and the mature flower heads are nodding on distinct pedicels.

Morphological similarities to both A. tournefortiana and A. magellanica have been noted and may be considered as conspecific.

Prevention and Control

Top of page

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.


Cultural Control and Sanitary Measures

Some control of infestations can be accomplished by pulling or mowing several times before seed heads mature (Blatchley, 1912; Pammel et al., 1913) and tillage is one of the most effective control methods (Lewis, 2012).

Chemical Control

Tolerance to several classes of herbicides and to other human manipulations has allowed this species to thrive in crop habitats and to expand its range (Johnson et al., 2004). In North America, A. biennis is increasing primarily in soyabean and dry bean cultivation because of its tolerance to many of the herbicides applied to these crops (Kegode and Christoffers, 2003). Tolerance was confirmed for several ALS (acetolactate synthase) inhibitors, dinitroanalines, HPPD (hydroxyphenylpyruvate dioxygenase) inhibitors, PPO (protoporphyrinogen oxidase) inhibitors, acetamides, and some growth regulators (e.g. bromoxynil and fluoxypyr) (Kegode et al., 2007).

Good to excellent (81-100%) pre-emergence control can be achieved with flumetsulam, flumioxazin, isoxaflutole, metribuzin and sulfentrazone (Kegode, 2000; Fronning and Kegode, 2004a, 2004b; Kegode et al., 2007). Flumetsulam is one of the few ALS-inhibiting herbicides that can control A. biennis. Post-emergence control must be initiated when seedlings are less than 8 cm in height to achieve greater than 80% control (Fronning and Kegode, 2004a; Kegode and Fronning, 2005). Atrazine, bentazon, clopyralid, dicamba, glufosinate, glyphosate, MCPA, and 2,4-D can provide 80% control. As a result of indeterminate emergence, greater than 90% control can be achieved with split applications of bentazon or glyphosate but required application rates will depend on the size of the young plants (Kegode and Fronning, 2005).


Top of page

Bisby GR, Buller AHR, Dearness J, Fraser WP, Russel RC, Gussow HT, 1938. The Fungi of Manitoba and Saskatchewan. Ottawa, Canada: National Research Council of Canada.

Blackshaw RE, Thomas AG, Derksen DA, Moyer JR, Watson PR, Légère A, Turnbull GC, 2006. Examining tillage and crop rotation effects on weed populations in the Canadian Prairies. In: Handbook of sustainable weed management [ed. by Singh, H. P.\Batish, D. R.\Kohli, R. K.]. Binghamton, USA: Food Products Press, 179-207.

Blatchley WS, 1912. The Indiana weed book. Indianapolis, Indiana, USA: The Nature Publishing Company, 191 pp.

Brenckle JF, 1917. North Dakota fungi: I. Mycologia, 9:275-293.

Cronquist A, 1994. Intermountain flora. Vascular plants of the Intermountain West, USA. Volume five. Asterales. Bronx, New York, USA: New York Botanical Garden, 496 pp.

Dorn RD, 1988. Vascular plants of Wyoming. Wyoming, USA: Mountain West Publishing, 340 pp.

Douglas GW Straley GB Meidinger DV Pojar J, 1998. Illustrated Flora of British Columbia, Volume 2. Victoria, Canada: BC Ministry of Environment, Lands and Parks and BC Ministry of Forests.

Drummond T, 1830. Botanical Miscellany, Volume 1 [ed. by Hooker, W. J.]. London, UK: John Murray, 178-219.

Erskine DS, 1961. The plants of Prince Edward Island. Research Branch, Canada Department of Agriculture, Publication 1088., Canada: Canada Department of Agriculture, 270 pp.

Euro+Med PlantBase, 2011. Euro+Med PlantBase: The information resource for Euro-Mediterranean plant diversity. Palermo, Italy.

Farlow WG, 1884. Additions to the Peronosporeae of the United States. Botanical Gazette, 9:37-40.

Fernald ML, 1950. Gray's Manual of Botany. Eighth Edition. New York, USA: American Book Company.

Fletcher J, 1907. Weeds. Bulletin No. 28. Ottowa, Ontario, Canada: Canada Department of Agriculture, 43 pp.

Frank JA, 1981. Rhizoctonia canker (Black scurf). In: Compendium of potato diseases [ed. by Hooker, W. J.]. St Paul, Minnesota, USA: American Phytopathological Society, 52-54.

Fronning BE, Kegode G, 2004. Biennial wormwood (Artemisia biennis) postemergence control in soybean. Weed Technology, 18(2):380-387.

Fronning BE, Kegode GO, 2004. Biennial wormwood (Artemisia biennis) early-season control with herbicides. Weed Technology, 18(3):611-618.

Gray A, 1848. Manual of the botany of the northern United States, 1st edition. London, UK: James Munroe and Company, 710 pp.

Gray A, 1867. Manual of the botany of the northern United States, 5th edition. New York, USA: Ivison, Blakeman, Taylor, 703 pp.

Groh H, 1944. Canadian weed survey second annual report 1943. Ottawa, Ontario, Canada: Department of Agriculture, 74 pp.

Gulden RH, 2009. Proceedings of the Manitoba Agronomists Conference 2009.

Gut D, Weber E, 1999. New problem plants and weeds in Switzerland. Agrarforschung, 6(10):401-403

Hall HM, Clements FE, 1923. The phylogenetic method in taxonomy: the North American species of Artemisia, Chrysonthanamus and Atriplex. Washington, DC, USA: Cargegie Institution of Washington, 355 pp.

Hegi G, 1929. Illustrierte Flora von Mittel-Europa. Volume 6, Part 2. Munich, Germany: JF Lehmans Verlag, 837 pp.

Hooker WJ, 1840. Flora Boreali-Americana. Volume 1. London, UK: HJ Bohn, 351 pp.

Jehlík V, 1984. Artemisia biennis in Czechoslovakia. Preslia, 36:319-328.

Johnson WG, Hartzler RG, Nordby DE, 2004. Weeds to watch: weeds that seem to be expanding their habitat range. North Central Weed Science Society, 59:133.

Kartesz JT, 2014. North American plant atlas. Chapel Hill, North Carolina, USA: The biota of North America program (BONAP).

Kegode G, Zollinger R, Cernia N, 2007. The glyphosate, weeds and crop series: biology and management of biennial wormwood. North Dakota State University Extension Service Publication W1322. North Dakota, USA: North Dakota State University, 12 pp.

Kegode GO, 2000. Biennial wormwood (Artemisia biennis): an emerging weed problem in the northern Great Plains. Proceedings of the Weed Science Society of America, 40:18.

Kegode GO, Christoffers MJ, 2003. Biennial wormwood (Artemisia biennis Willd.). Weed Technology, 17(3):646-649.

Kegode GO, Ciernia MG, 2005. Biennial wormwood allelopathic potential. Weed Science Society of America, 45:187.

Kegode GO, Darbyshire SJ, 2013. The Biology of Canadian Weeds. 152. Artemisia biennis Willd. Canadian Journal of Plant Science, 93(4):643-658.

Kegode GO, Fronning BE, 2005. Artemisia biennis (biennial wormwood) control is influenced by plant size and weed flora at time of herbicide application. Crop Protection, 24(10):915-920.

Knuth P, 1908. Handbook of flower pollination. Volume 2. Oxford, UK: Clarendon Press.

Kreitschitz A, 2012. Mucilage formation in selected taxa of the genus Artemisia L. (Asteraceae, Anthemideae). Seed Science Research, 22(3):177-189.

Lewis DW, 2012. Kochia (Kochia scoparia (L.) Schrad.) and biennial wormwood (Artemisia biennis Willd.) interface with sunflower (Helianthus annuus L.), Masters Thesis. Winnipeg, Manitoba, Canada: University of Manitoba, 124 pp.

Lin Y, Humphries CJ, Gilbert MG, 2011. Artemisia Linnaeus. In: Flora of China. Volume 20-21 (Asteraceae) [ed. by Wu, Z. Y. \Raven, P. H. \Hong, D. Y.]. Bejing and Missouri, China and USA: Science Press and Missouri Botanical Garden Press, 676-737.

Ling Y-R, 1995. The New World Artemisia L. In: Advances in Compositae systematics [ed. by Hind, D. N. \Jeffrey, C. \Pope, G. V.]. Kew, Richmond, USA: Royal Botanic Gardens Kew, 255-281.

Lopes-Lutz D, Alviano DS, Alviano CS, Kolodziejczyk PP, 2008. Screening of chemical composition, antimicrobial and antioxidant activities of Artemisia essential oils. Phytochemistry, 69(8):1732-1738.

Löve Á, Löve D, 1982. IOPD chromosome number reports LXXV. Taxon, 31:342-368.

Macoun J, 1883. Catalogue of Canadian plants. Part I. -- Polypetalae. Montreal, Quebec, Canada: Dawson Brothers, 623 pp.

Mahoney KJ, Kegode GO, 2004. Biennial wormwood (Artemisia biennis) biomass allocation and seed production. Weed Science, 52(2):246-254.

Meisner A, Boer Wde, Verhoeven KJF, Boschker HTS, Putten WHvan der, 2011. Comparison of nutrient acquisition in exotic plant species and congeneric natives. Journal of Ecology (Oxford), 99(6):1308-1315.

Mengistu LW, Christoffers MJ, Kegode GO, 2004. Genetic diversity of biennial wormwood. Weed Science, 52(1):53-60.

Mulligan GA, Findlay JN, 1970. Reproductive systems and colonization in Canadian weeds. Canadian Journal of Botany, 48(5):859-860.

Nematollahi F, Rustaiyan A, Larijani K, Nadimi M, Masoudi S, 2006. Essential oil composition of Artemisia biennis Willd. and Pulicaria undulate (L.) C.A. Mey., two compositae herbs growing wild in Iran. Journal of Essential Oil Research, 18:339-341.

Pammel LH, 1913. The Weed Flora of Iowa. Des Moines, USA: Iowa Geological Society.

Pellicer J, Garnatje T, Molero J, Pustahija F, Siljak-Yakovlev S, Vallès J, 2010. Origin and evolution of the South American endemic Artemisia species (Asteraceae): evidence from molecular phylogeny, ribosomal DNA and genome size data. Australian Journal of Botany, 58(7):605-616.

Powell AM, Kyhos DW, Raven PH, 1974. Chromosome numbers in Compositae. X. American Journal of Botany, 61:909-913.

Rousseau C, 1968. [English title not available]. (Histoire, habitat et distribution de 220 plantes introduites au Québec.) Le Naturaliste Canadien, 95:49-171.

Schultz LM, 2006. Artemisia Linnaeus. In: Flora of North America north of Mexico, Volume 19. Magnoliophyta: Asteridae, Part 6: Asteraceae, Part 1 [ed. by Barkley, T. M.]. New York, USA: Oxford University Press, 503-534.

Shoemaker RA, 1976. Canadian and some extralimital Ophiolobus species. Canadian Journal of Botany, 54:2365-2404.

Sood SK, Nath R, Kalia DC, 2001. Ethnobotany of cold desert tribes of Lahaul-Spiti (N. Himalaya). New Delhi, India: Deep Publication, 228 pp.

Stace C, 1997. New flora of the British Isles, 2nd edition., UK: Cambridge University Press, 1130 pp.

Stevens OA, 1932. The number and weight of seeds produced by weeds. American Journal of Botany, 19:784-794.

Stevens OA, 1950. Handbook of North Dakota plants. Fargo, North Dakota, USA: North Dakota Agricultural College, 324 pp.

Suominen J, 1979. The grain immigrant flora of Finland. Acta Botanica Fennica, 111:1-108.

Thomas JH, 1961. Flora of the Santa Cruz mountains of California. Stanford, California, USA: Stanford University Press, 434 pp.

US Fish and Wildlife Service, 2013. In: Endangered and Threatened Wildlife and Plants; Endangered Status for Gunnison Sage-Grouse; Proposed Rule. 78(8) US Fish and Wildlife Service, 2486-2538.

USDA-ARS, 2015. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory.

Vallès J, McArthur ED, 2001. Artemisia systematics and phylogeny: cytogenetic and molecular insights. Shrubland ecosystem genetics and biodiversity [ed. by McArthur, E. D. \Fairbanks, D. J.]. Povo, Utah, USA: US Department of Agriculture Forest Service Rocky Mountain Research Station, 67-74.


Top of page

23/03/2015 Original text:

Stephen Darbyshire and Ardath Francis, Agriculture and Agri-Food, Canada

Distribution Maps

Top of page
You can pan and zoom the map
Save map