''Conyza'' (horseweed, butterweed or fleabane) is a genus of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of ...

s in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae ...

. They are native to tropical and warm temperate regions throughout the world, and also north into cool temperate regions in North America and eastern

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

. The

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. ...

species of the genus are closely related to '' Erigeron'' (also known as fleabanes).Flora of North America, Horseweed, ''Conyza'' Lessing
/ref> The species are annual or

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition ...

plants, rarely shrubs, growing to 1–2 m tall. The stems are erect, branched, with alternate leaves. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism ...

s are produced in

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed ...

s, with several inflorescences loosely clustered on each stem. Many species of the genus ''Conyza'' are ruderal species and some have been found to be resistant to the herbicide glyphosate. ; Species

References

External links

Germplasm Resources Information Network: ''Conyza''

Chinese plant names: ''Conyza''
{{Taxonbar, from=Q828737 Astereae Asteraceae genera Ruderal species