''Senecio triangularis'', known as arrowleaf ragwort, arrowleaf groundsel and arrowleaf butterweed, is a

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

Senecio ''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Morp ...

'' and 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 ...

Description

It is similar in form to ''Senecio serra'', both being four feet tall, have narrow and serrated leaves, and are topped with many small, yellow sunflowers. but S. triangularis is more common than S. serra. S. triangularis has single erect stems, reaching up to tall. The stems have evenly distributed leaves. The leaves are triangular, with tapered ends, hence the name. As some plants are

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respecti ...

, meaning having two sets of

chromosomes A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

, this can be used to identify hybrids and classification of groupings. It has been counted as 2n = 40, 80. It is

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and enterta ...

to temperate regions of America and is reportedly poisonous to animals.

Taxonomy

It has the common names of arrowleaf ragwort, arrowleaf groundsel, and arrowleaf butterweed. In the early 1830s, Scottish botanist

Thomas Drummond Captain Thomas Drummond (10 October 1797 – 15 April 1840), from Edinburgh was a Scottish army officer, civil engineer and senior public official. He used the Drummond light which was employed in the trigonometrical survey of Great Britain an ...

collected this plant, probably on his second trip to the United States. The plant was named by William Hooker, Drummond's mentor, and first published and described by

Hooker Hooker may refer to: People * Hooker (surname) Places Antarctica * Mount Hooker (Antarctica) * Cape Hooker (Antarctica) * Cape Hooker (South Shetland Islands) New Zealand * Hooker River * Mount Hooker (New Zealand) in the Southern Alps * Hoo ...

in 'Flora Boreali-Americana' (Fl. Bor.-Amer.) Vol.1 on page 332 in 1834.

Distribution

;Native: :

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: ::Subarctic America: Northwest Territory,

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::Western Canada:

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::Northwestern United States:

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::Southwestern United States:

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Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

Source: GRIN,

Habitat

It grows in open woodlands, (mainly coniferous forests) and on rocky stream sides. They can grow at altitudes of between .

References

External links

triangularis The depressor anguli oris muscle (triangularis muscle) is a facial muscle. It originates from the mandible and inserts into the angle of the mouth. It is associated with frowning, as it depresses the corner of the mouth. Structure The depresso ...

Alpine flora Flora of Subarctic America Flora of Western Canada Flora of the Northwestern United States Flora of the West Coast of the United States Flora of the Southwestern United States Flora of the Sierra Nevada (United States) Flora of the Rocky Mountains Flora without expected TNC conservation status {{Senecioneae-stub