Galinsoga quadriradiata (Hairy galinsoga)

Galinsoga quadriradiata Cav.

Hairy galinsoga, shaggy soldier

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Asteridae	A large class that encompasses asters
Order	Asterales	Flowering plants with a central disk flower and surrounding petals, like daisies
Family	Asteraceae	The aster family, which also includes daisies and sunflowers; from the Greek ἀστήρ, “star,” for the star-shaped flowers
Genus	Galinsoga	Named for 18th century Spanish doctor and director of Jardin Botanique de Madrid, Ignacio Mariano Martinez de Galinsoga
Species	quadriradiata	With four ray florets or with four radiating structures

About plant names...

Hairy galinsoga is a widespread weed that is easily overlooked, with small flowers and few distinctive features, unless you are a farmer and it is ruining your crop yields. These inconspicuous weeds can reduce crop yields by 50%. They are believed to have originated in Mexico.

Identification: Plants are 4-31" (10-80 cm) high, often branched; stems are covered with short hairs. Leaves are opposite, medium to dark green, and up to 2" (6 cm) × 1½" (4 cm). They are broadest at the base, tapering to a tip, sparsely to densely hairy, and coarsely toothed. Flowers are ¼-⅜" (6.3-10 mm) in diameter, with 4 or 5 petals, each with three teeth; and a central yellow disk. Fruits are small achenes with little plumes.

References:

Old, Richard, 1200 Weeds of North America DVD, XID Services, Inc., 2012

Online References:

Galinsoga quadriradiata on Discover Life

Galinsoga quadriradiata at Illinois Wildflowers

Galinsoga quadriradiata on

Galinsoga quadriradiata on www.gri.msstate.edu

Galinsoga quadriradiata on the USDA Plants Database

Galinsoga quadriradiata at Minnesota Wildflowers

Galinsoga quadriradiata on eFloras

Galinsoga aristulata E.P. Bicknell

Galinsoga bicolorata H. St. John & D. White