Synonyms: Ambrosia absynthifolia (Michx., 1803), Ambrosia artemisiifolia L. subsp. diversifolia (Piper, 1837), Ambrosia artemisiifolia L. var. jamaicensis (Griseb. 1861), Ambrosia artemisiifolia L. var. octocornis (Kuntze, 1891), Ambrosia artemisiifolia L. var. quadricornis (Kuntze, 1891), Ambrosia artemisiifolia var. artemisiifolia, Ambrosia artemisiifolia var. elatior (Descourt., 1821), Ambrosia artemisiifolia var. elatior f. villosa (Fernald & Griscom, 1935), Ambrosia artemisiifolia var. paniculata (Michx.), Ambrosia diversifolia (Piper), Ambrosia elata (Salisbury, 1796), Ambrosia elatior L., Ambrosia elatior L. var. heterophylla (Muhlenburg ex Willedenow, 1913), Ambrosia glandulosa (Scheele, 1849), Ambrosia heterophylla (Muhlenburg ex Willdenow, 1803), Ambrosia longistylus (Nuttall, 1840), Ambrosia media (Rydberg, 1910), Ambrosia monophylla (Rydberg, 1922), Ambrosia paniculata (Michaux, 1803, Ambrosia simplicifolia (Raeuschel, 1797), Iva monophylla (Walter, 1788)
Common names: ambroisie à feuille d’armoise (French-France), ambroisie annuelle (French-France), ambroisie élevée (French-France), ambrosia aux feuilles d’armoise (French-France), ambrosia con foglie di atremisia (Italian-Italy), ambrosia de hojas de ajenjo (Spanish), ambrozja bylicolistna (Poland), ambrozja bylicowata (Poland), annual ragweed (English), artemisia del pais (Spanish), Aufrechte Ambrosie (German-Germany), Aufrechtes Traubenkraut (German-Switzerland), bastard wormwood (English-United Kingdom), Beifußambrosie (German-Germany), Beifussblättriges Ambrosie (German-Germany), Beifussblättriges Traubenkraut (German-Germany), beiskambrosia (Norway), bitterweed (English), blackweed (English-Canada), bynke-ambrosie (Danish-Denmark), carrot-weed (English-Canada), common ragweed (English), hay-fever weed (English-Canada), hog-weed (English), Hohes Traubenkraut (German-Germany), kietine ambrozija (Lithuanian-Lithuania), low ragweed (English), malörstambrosia (Sweden), marunatuoksukki (Finland), parlagfu (Hungary), petite herbe à poux (French-Canada), pujulehine ambroosia (Estonia), ragweed (English), roman bitterweed (English-Canada), Roman wormwood (English), römischer Wermut (German-Germany), Shinners ragweed (English-South Korea), short ragweed (English), small ragweed (English), Stalin weed (English-Hungary), stammerweed (English-Canada), stickweed (English-Canada), vadkender (Hungary), vermellapu ambrozija (Latvian-Latvia), wild tansy (English-Canada)
Other Names : Annual Ragweed, Bitterweed, Blackweed, Carrot Weed, Hay Fever Weed, Roman Wormwood, Stammerwort, Stickweed, Tassel Weed, Wild Tansy, and American Wormwood.
Habitat : N. America – British Columbia to Nova Scotia and Florida. it is invasive in some European countries and Japan, known as butakusa Locally established casual in Britain. Waste places in Western N. America. Found in dry soils, it can become a pernicious weed in cultivated soils.
Ambrosia artemisiifolia is a summer annual herbaceous plant that is erect, with many branches (AWCNI, undated) and can reach heights between 1-2 metres (NRW, 2007) with a grooved, reddish, hairy stem (Wittenberg, R. (ed.) 2005). The leaves are opposite, compound, and toothed (Wittenberg, R. (ed.) 2005) reaching lengths of 4-10cm long (VTWIG, undated). The tops of the leaves are green and hairy, with white hairs adpressed on the underside of the leaf (Wittenberg, R. (ed.) 2005). Male flowers are green, small, 4-5mm, with bractless flowers arranged in a terminal spike located in the upper portions of the plant (Wittenberg, R. (ed.) 2005), often drooping (AWCNI, undated). The female flowers are located in the axils of the upper leaves, sessile, and inconspicuous in either small clusters or singly (Wittenberg, R. (ed.) 2005). The fruit of the common ragweed is a woody achene, 3-4mm long and 1-2mm wide, with 4-7 spine-like projections, resembling a crown (VTWIG, undated). The leaves are bright green on both sides with whitish nerves. On older plants the lower leaves can be arranged opposite and the upper leaves can be alternately arranged on the stem (C. Bohren., pers.comm., 2007).
It is hardy to zone 0. It is in flower from August to October. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by Wind. Common Ragweed emerges in the late spring and sets seed in later summer or fall.
Common ragweed is a very competitive weed and can produce yield losses in soybeans as high as 30%. Control with night tillage reduces emergence by around 45%. Small grains in rotation will also suppress common ragweed if they are overseeded with clover. Otherwise, the ragweed will grow and mature and produce seed in the small grain stubble. Several herbicides are effective against common ragweed, although resistant populations are known to exist
The plant prefers light (sandy), medium (loamy) and heavy (clay) soils. The plant prefers acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It requires moist soil.
We have very little information on this species but suggest growing it in a sunny position in a well-drained soil. It has been suggested for commercial cultivation. Some plants produce mainly sterile heads. The pollen from the flowers of this species is an important cause of hay-fever in N. America.
Seed – we have no details for this species but suggest sowing the seed in situ in April.
An essential oil of Ambrosia artemisiifolia acts as an antimicrobial, having antibacterial and antifungal compounds.
Edible Uses: Oil.
An oil is obtained from the seed. It has been suggested for edible purposes because it contains little linolenic acid. The seed contains up to 19% oil, it has slightly better drying properties than soya bean oil.
Medicinal Actions & Uses
Antidote; Astringent; Disinfectant; Emetic; Febrifuge; Women’s complaints.
The leaves are very astringent, emetic and febrifuge. They are applied externally to insect bites, rheumatic joints and various skin complaints, internally they are used as a tea in the treatment of fevers, pneumonia, nausea, intestinal cramps, diarrhoea and mucous discharges. Juice from the wilted leaves is disinfectant and is applied to infected toes. A tea made from the roots is used in the treatment of menstrual disorders and stroke. The pollen is harvested commercially and manufactured into pharmaceutical preparations for the treatment of allergies to the plant.
Known Hazards : The pollen of this plant is a major cause of hayfever in N. America. Ingesting or touching the plant can cause allergic reactions in some people.
Disclaimer:The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplements, it is always advisable to consult with your own health care provider.