Ambrosia artemisiifolia

Basic information
Scientific name	Ambrosia artemisiifolia	Click to magnify
Major synonym	Ambrosia artemisiifolia var. elatior
Common names	Bitterweed, Common Ragweed, hogweed, Annual ragweed
Higher taxon	Asteraceae, Asterales, Magnoliopsida, Magnoliophyta
Natural range	North America.
Habitat	Farm area, fruit garden, pasture field, lawn field, roadside, vacancy, edge of forest, river side, etc.

Invasion information
Range in Japan	Almost entire Japan including Okinawa.
Origin	Unknown.
Date	The first introduction was ca. 1877. Establishment was ca. 1925 or later. A specimen record was in 1972.
Route	Accidental: Details unknown.
Impact	Actually: Competition with native species, crops, lawn grasses. Allelopathy. Parasite (insects, fungi, viruses, parasitic grass genus Cuscuta). Allergen for hay fever. Native organism(s) affected: Native grasses, crops, lawn grasses, etc (competition). Human (health damage).
Regulation in Japan	No action for prevention, mitigation, control, or eradication.
Introduced range in other countries	South America, Europe, Asia, and Australia.

Reference	Notes
Hotta et al. (1989) Useful Plants of the World. Heibonsha, Tokyo (in Jpn) Jpn Assoc Advanc Phyto-Regul & Inst Contr Agrochem, Minist Agr, China (2000) Chinese Colored Weed Illustrated Book. Zenkoku-Noson-Kyoiku-Kyokai, Tokyo Osada (1976) Colored Illustrations of Naturalized Plants of Japan. Hoikusha, Osaka (in Jpn) Shimizu (ed) (2003) Naturalized Plants of Japan. Heibonsha, Tokyo (in Jpn) etc.	South Korea prohibits importation of this species.