''Sherardia'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

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 nom ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Rubiaceae The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with interpetiolar stipules a ...

. The genus contains only one

species In biology, a species is the basic unit of 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 the appropriate s ...

, viz. ''Sherardia arvensis'' or (blue) field madder, which is widespread across most of

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

and northern

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

as well as southwest and central Asia (from

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula in ...

Saudi Arabia Saudi Arabia, officially the Kingdom of Saudi Arabia (KSA), is a country in Western Asia. It covers the bulk of the Arabian Peninsula, and has a land area of about , making it the fifth-largest country in Asia, the second-largest in the A ...

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...

) and

Macaronesia Macaronesia (Portuguese: ''Macaronésia,'' Spanish: ''Macaronesia'') is a collection of four volcanic archipelagos in the North Atlantic, off the coasts of Africa and Europe. Each archipelago is made up of a number of Atlantic oceanic islands ...

( Canary Islands,

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

, Madeira,

Savage Islands The Savage Islands or Selvagens Islands ( pt, Ilhas Selvagens ; also known as the Salvage Islands) are a small Portuguese archipelago in the North Atlantic Ocean, south of Madeira, and north of the Canary Islands.30,000), white-faced storm- ...

). It is also reportedly naturalized in Australia,

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

Kerguelen The Kerguelen Islands ( or ; in French commonly ' but officially ', ), also known as the Desolation Islands (' in French), are a group of islands in the sub-Antarctic constituting one of the two exposed parts of the Kerguelen Plateau, a large ...

Ethiopia Ethiopia, , om, Itiyoophiyaa, so, Itoobiya, ti, ኢትዮጵያ, Ítiyop'iya, aa, Itiyoppiya officially the Federal Democratic Republic of Ethiopia, is a landlocked country in the Horn of Africa. It shares borders with Eritrea to the ...

, Sudan, southern

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, Costa Rica,

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

Bermuda ) , anthem = "God Save the King" , song_type = National song , song = "Hail to Bermuda" , image_map = , map_caption = , image_map2 = , mapsize2 = , map_caption2 = , subdivision_type = Sovereign state , subdivision_name = , es ...

Cuba Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...

, Haiti and much of

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

and the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

(especially the

Pacific States The West Coast of the United States, also known as the Pacific Coast, Pacific states, and the western seaboard, is the coastline along which the Western United States meets the North Pacific Ocean. The term typically refers to the contiguous U.S ...

and the lower

Mississippi Valley The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it ...

Description

''Sherardia arvensis'' is an annual plant with trailing and upright stems growing up to 40 cm long, having a square cross-section. The rough pointed bristly leaves of about 1 cm in length are in

whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral ...

of four to six (normally six at the ends of the shoots, but four nearer the root). The tiny pale lilac or pink flowers are approximately 3 mm in diameter and have a long tube, with only the end part of the four petals free. The flowers grow in clusters of two or three together in an involucral structure formed out of a ring of six

bracts In botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the An ...

. The fruit are dry and about 3 mm long with two lobes giving rise to two small, dry, indehiscent fruits called nutlets. The four-angled stems with whorls of bristly leaves and tiny flowers are reminiscent of the Bedstraws and other related

, but ''Sherardia'' is distinguished by its mauve/pink flowers that are organized in clusters and having a long corolla tube. ''Sherardia arvensis'' plants are hermaphroditic and pollinated by flies.Plants for a Future - Sherardia arvensis
/ref>

Uses

''Sherardia arvensis'' is a common weed of fields, pasture, grassland, and disturbed areas. The fleshy roots, though much inferior to the common madder ('' Rubia tinctorum''), are sometimes used for the production of a red dye.

Taxonomy

The genus and species were described by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...

in '' Hortus Cliffortianus'' in 1736 and also appeared in his masterwork '' Species Plantarum'' in 1753. The genus was named in memory of the prominent English botanist

William Sherard William Sherard (27 February 1659 – 11 August 1728) was an English botanist. Next to John Ray, he was considered to be one of the outstanding English botanists of his day. Life He is still a little-known figure of that era coming as he did from ...

(1659–1728). The Latin epithet ''arvensis'' means that it is found in fields.

Image gallery

File:Sherardia arvensis Kaldari 01.jpg File:Sherardia arvensis Kaldari 02.jpg File:72 Sherardia arvensis.jpg

References

External links

''Sherardia'' in the World Checklist of RubiaceaeUSDA Plants Profile

Wildflowers of the United States, ''Sherardia arvensis'' Calflora taxon report, ''Sherardia arvensis''
* ttp://www.tela-botanica.org/bdtfx-nn-63722-synthese Tela Botanica, ''Sherardia arvensis'' br>News from Rockcliff Farm, Natural Gardens of North Carolina, Blue Field-Madder, ''Sherardia arvensis''
* ttp://www.floravascular.com/index.php?spp=Sherardia%20arvensis Flora Vascular, ''Sherardia arvensis'' br>Wilde Planten in Nederland dn Belgie, Blauw walstro, Blauslyt, Field Madder, Rubéole des champs, Ackerröte, ''Sherardia arvensis''
{{Taxonbar, from1=Q14566705, from2=Q158352 Flora of Europe Flora of Asia Flora of Africa Monotypic Rubiaceae genera Rubieae