Galinsoga is a genus of annual flowering herbs in the daisy family Asteraceae, order Asterales. The genus comprises a small number of species native to the Americas — principally South America and central Mexico — that have become some of the world's most successful weedy colonizers, now naturalized across Europe, Asia, Africa, and Australasia.
Plants in the genus are branched herbs typically 25–75 cm tall, with opposite, stalked leaves that are toothed at the margins. The flower heads are small, each bearing a ring of white ray florets surrounding a cluster of yellow tubular disc florets — a classic composite-flower structure. The two best-known species differ in hairiness: G. parviflora (gallant soldier, quickweed) is largely glabrous, while G. quadriradiata (shaggy soldier, Peruvian daisy) is sparsely to densely hairy with a mixture of glandular and simple hairs.
The genus was named in honor of Ignacio Mariano Martinez de Galinsoga, the Spanish physician who founded the Real Academia Nacional de Medicina and directed the Real Jardín Botánico de Madrid in the late eighteenth century. Galinsoga parviflora was introduced to Britain via Kew Gardens in 1796 and subsequently escaped, earning the popular nickname "Kew Weed" before spreading across the country.
Both principal species are edible and have a long history of use as pot herbs and salad greens across their native and naturalized ranges, particularly in Colombia, Mexico, and parts of Africa.
Etymology
The genus Galinsoga was named in honor of Ignacio Mariano Martinez de Galinsoga (1760–1797), a Spanish physician who founded the Real Academia Nacional de Medicina and served as director of the Real Jardín Botánico de Madrid. The species epithet of its best-known member, parviflora, is Latin for "having small flowers."
Distribution
Galinsoga is native to South America and central Mexico. Both major species — G. parviflora and G. quadriradiata — have spread far beyond their native range and are now naturalized across Europe, North America, Australasia, Japan, the Philippines, northern India, Nepal, and much of sub-Saharan Africa. G. parviflora was first recorded in Britain after escaping from Kew Gardens in 1796.
Ecology
Both Galinsoga species are fast-growing annuals that thrive in disturbed habitats — cultivated fields, roadsides, gardens, and waste ground. Their prolific branching (producing side shoots at nearly every node in G. quadriradiata) and abundant seed production make them persistent agricultural weeds in temperate and subtropical regions worldwide.
Cultural Uses
Galinsoga parviflora is an important culinary herb in several countries. In Colombia it is an essential ingredient in ajiaco, a traditional potato and chicken soup. In Oaxaca, Mexico, it is used in sopa de guías, a broth of squash vines, fresh corn, and wild herbs. The plant has a subtle flavor reminiscent of artichoke that develops more fully after cooking; it can also be eaten raw in salads. In eastern Africa, leaves, stems, and flowers are collected from the wild and consumed fresh or dried and ground into a powder for soups. G. quadriradiata is also edible and used similarly, though its hairy leaves make it less preferred as a salad green.
History
Galinsoga parviflora was introduced to Europe when specimens were brought from Peru to Kew Gardens in 1796. The plant soon escaped cultivation and spread across Britain and Ireland, where it was briefly called "Kew Weed." Its English colloquial name "gallant soldiers" derives from a popular rendering of the botanical name Galinsoga, which was sometimes further altered to "soldiers of the Queen."
