Common Ragweed (Ambrosia artemisiifolia) also known as: Annual Ragweed, Bitterweed, Hay-Fever Weed, Hog-Weed, Mayweed, Roman Wormweed, Wild Tansy, etc. Division - Magnoliaphyta Class - Magnoliopsida Subclass - Asteridae Order - Asterales Family - Asteraceae Genus - Ambrosia Status - Annual Weeds Taxonomic List List by Scientific Name