Erigeron canadensis | |
---|---|
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Genus: | Erigeron |
Species: | E. canadensis |
Binomial name | |
Erigeron canadensis | |
Synonyms [1] | |
Alphabetical list
|
Erigeron canadensis (synonym Conyza canadensis) is an annual plant native throughout most of North America and Central America. It is also widely naturalized in Eurasia and Australia. Common names include horseweed, Canadian horseweed, Canadian fleabane, coltstail, marestail, and butterweed. It was the first weed to have developed glyphosate resistance, reported in 2001 from Delaware.
Erigeron canadensis is an annual, herbaceous plant growing to 1.5 metres (5 feet) tall, with sparsely hairy stems. The leaves are unstalked, slender, 2–10 centimetres (0.8–3.9 inches) long, and up to 1 cm (0.4 in) wide, with a coarsely toothed margin. They grow in an alternate spiral up the stem, and the lower ones wither early. The flower heads are produced in dense inflorescences and are 1 cm (0.4 in) in diameter. Each individual flower has a ring of white or pale purple ray florets and a centre of yellow disc florets. The fruit is a cypsela tipped with dirty white down. [2]
Erigeron canadensis can easily be confused with Erigeron sumatrensis , which may grow to a height of 2 m (6.6 ft), and the more hairy Erigeron bonariensis , which does not exceed 1 m (3.3 ft). E. canadensis is distinguished by bracts that have a brownish inner surface with no red dot at the tip, and are free (or nearly free) of the hairs found on the bracts of the other species. [3] [4] [5]
Horseweed originated in North America and Central America and is widespread in its native range. [6] It has spread to inhabited areas of most of the temperate zone of Asia, [7] Europe, [2] [8] and Australia. [9] It is found in Britain from northern Scotland to Cornwall, growing as a weed of arable land and man-made environments. It is considered invasive in China. [10]
Horseweed is commonly considered a weed, and in Ohio, Oregon, and some other locations, [11] it has been declared a noxious weed. [12] [13] It was the first weed to have developed glyphosate resistance, reported in 2001 from Delaware. [14]
It can be found in fields, meadows, and gardens throughout its native range. Horseweed infestations (specifically of 105 plants per 10 ft²) have reduced soybean yields by as much as 83%, [15] with one estimate claiming it can reduce yields by up to 90%. [16] Severe infestations have reduced sugar beet yields by 64%. [15]
It is an especially problematic weed in no-till agriculture, as it is often resistant to glyphosate [14] and other herbicides. [17] Farmers are advised to include 2,4-D or dicamba in a burndown application prior to planting to control horseweed. [18] [19]
The Zuni people insert the crushed flowers of E. canadensis var. canadensis into the nostrils to cause sneezing, relieving rhinitis. [20] Other[ who? ] Native Americans have used a preparation of the plant's leaves to treat sore throat and dysentery. [21] A tincture can be made from the dried flowering tops of the plants.[ citation needed ]
Horseweed is a preferable material for use in the hand drill-method of making friction fire. [2] [ failed verification ]
Erigeron is a large genus of plants in the composite family (Asteraceae). It is placed in the tribe Astereae and is closely related to the Old World asters (Aster) and the true daisies (Bellis). The genus has a cosmopolitan distribution, but the highest diversity occurs in North America.
Conyza is a genus of flowering plants in the family Asteraceae.
Erigeron bonariensis is a species in the family Asteraceae, found throughout the tropics and subtropics as a pioneer plant; its precise origin is unknown, but most likely it stems from Central America or South America. It has become naturalized in many other regions, including North America, Europe and Australia.
Centaurea calcitrapa is a species of flowering plant known by several common names, including red star-thistle and purple star thistle. It is native to Europe but is rarely found there, it is known across the globe as an introduced species and often a noxious weed. The species name calcitrapa comes from the word caltrop, a type of weapon covered in sharp spikes.
Amaranthus palmeri is a species of edible flowering plant in the amaranth genus. It has several common names, including carelessweed, dioecious amaranth, Palmer's amaranth, Palmer amaranth, and Palmer's pigweed.
Erigeron sumatrensis is an annual herb probably native to South America, but widely naturalised in tropical and subtropical regions, and regarded as an invasive weed in many places.
Erigeron philadelphicus, the Philadelphia fleabane, is a species of flowering plant in the composite family (Asteraceae). Other common names include common fleabane, daisy fleabane, frost-root, marsh fleabane, poor robin's plantain, skervish, and, in the British Isles, robin's-plantain, but all of these names are shared with other species of fleabanes (Erigeron). It is native to North America and has been introduced to Eurasia.
Erigeron annuus, the annual fleabane, daisy fleabane, or eastern daisy fleabane, is a species of herbaceous, annual or biennial flowering plant in the family Asteraceae.
Erigeron breweri is a North American species of flowering plants in the family Asteraceae known by the common name Brewer's fleabane.
Erigeron eatonii is a North American species of flowering plants in the family Asteraceae known by the common name Eaton's fleabane.
Anoda cristata is a species of flowering plant in the mallow family known by many common names, including spurred anoda, crested anoda, and violettas. It is native to North and South America. It is known throughout the rest of the Americas as well as Australia as an introduced species and often a noxious weed. It has been found as a weed in Belgium. Naturally, it is often found near streams, in moist meadows, and in disturbed areas.
Erigeron tener is a North American species of flowering plant in the family Asteraceae known by the common name slender fleabane. It is native to the western United States, largely in the Great Basin, in the states of California, Arizona, Nevada, Utah, Oregon, Wyoming, Idaho, and Montana.
Erigeron lonchophyllus is an Asian and North American species of flowering plant in the family Asteraceae known by the common name shortray fleabane.
Erigeron pulchellus, the Robin's plantain, blue spring daisy or hairy fleabane, is a North American species of plants in the family Asteraceae. It is widespread across much of the United States and Canada from Québec and Ontario south as far as eastern Texas and the Florida Panhandle.
Erigeron pumilus, the shaggy fleabane, or vernal daisy, is a hairy North American species of perennial plants in the family Asteraceae. It is widespread across much of western Canada and the western United States, from British Columbia east to Saskatchewan and south as far as Oklahoma and the San Bernardino Mountains of California. There have been reports of the plant growing in Yukon Territory, but these were based on misidentified specimens.
Conyza ramosissima, the dwarf horseweed, is a species of North American plants in the family Asteraceae. It is widespread and common across the central part of the United States, its range extending from New Mexico east to Alabama and north as far as Pennsylvania, Ontario, and North Dakota.
Erigeron poliospermus is a species of flowering plant in the family Asteraceae known by the common names gray-seeded fleabane, purple cushion fleabane, and hairy-seed fleabane. Native to western North America, it is mainly found to the east of the Cascade Range in Washington, Oregon, and Idaho.
Erigeron floribundus is an annual/biennial plant native to South America to Mexico and introduced to many parts of the world. Its common names include tall fleabane, Bilbao's fleabane, and many-flowered fleabane.
Media related to Erigeron canadensis at Wikimedia Commons