False asterisks

False asterisks
	Detail of the inflorescence with cup-shaped partial inflorescences of the New York mock aster ( Vernonia noveboracensis )
Systematics
	Euasterids II
Order :	Astern-like (Asterales)
Family :	Daisy family (Asteraceae)
Subfamily :	Cichorioideae
Tribe :	Vernonieae
Genre :	False asterisks
Scientific name
	Vernonia
	Schreb.

The bill asters or Vernonien ( Vernonia ) are a genus of flowering plants in the family of the daisy family (Asteraceae). There are around 20 species (previously around 1000 species were grouped together in this genus). All species according to today's narrow view (according to H. Robinson 1999) of the genus are common in the New World ; most species on the North American continent , only two to three species in South America and one species in the Bahamas .

description

Illustration from The native flowers and ferns of the United States in their botanical, horticultural and popular aspects, 1879 der New York-Scheinaster ( Vernonia noveboracensis )

Inflorescence with cup-shaped partial inflorescences of Vernonia baldwinii

High false aster ( Vernonia gigantea )

Vernonia lettermanii

New York asterisk ( Vernonia noveboracensis )

Vegetative characteristics

The Schein aster species are large, perennial herbaceous plants that can usually reach heights of 20 to 200 centimeters, but also heights of more than 300 centimeters. Some species form rhizomes .

The stalked or sessile foliage leaves are seldom predominantly together in basal rosettes, mostly they are distributed on the stem. The shape of the leaf blades varies between egg-shaped, elliptical, lanceolate, obscure-lanceolate, spatulate, linear or thread-shaped. The base of the leaf blades is more or less wedge-shaped, with the exception of the species Vernonia pulchella with a rounded-off leaf base. The leaf margins are usually serrated, rarely entire, the leaf tips are pointed to pointed. The undersides of the leaves are usually more or less scaly to finely bristled or woolly to tomentose, sometimes hairless, usually covered with resin glands. The upper side of the leaf is scaly or smooth, only sometimes covered with resin glands.

Generative characteristics

In umbellate to paniculate total inflorescences with a diameter of (6 to) 10 to over 25 centimeters there are usually 40 to 100, but also significantly fewer (6) or more flower heads together without bracts. The cup-shaped inflorescences are more or less stalked and disc-shaped. The bracts are bell-shaped to inverted conical or hemispherical, 3 to 8, rarely up to 11 or more cm in diameter. Each 18 to over 70 bracts are in four to more than seven rows. The outer bracts are ovate to lanceolate or awl-shaped, the inner more or less lanceolate to oblong. All are more or less paper-like, with entire margins, often ciliated, the tips either rounded, then sometimes pointed, pointed, awl-shaped or thread-shaped. The surface is hairless or slightly provided with fine line bristles to tomentose, sometimes covered with glands. In each flower head there are only 9 to 30 (sometimes up to 65 or more) ray florets, depending on the species . The petals are fused into a tube, which is shaped into a tongue at the top, this has five corolla lobes, from which you can clearly see that the corolla tube is formed from five petals. The petals are usually purple or pink, rarely white. The five corolla lobes are lanceolate-linear and more or less the same shape.

The achenes are more or less columnar, sometimes curved in an arc. They have eight to ten ribs, are hairless or scaly to fine-bristled and often covered with resin glands. The persistent papus consists of 20 to more than 30 outer, irregularly serrated to awl-shaped scales or bristles, as well as 20 to more than 40 inner, awl-shaped to bristly scales or bristles.

The basic chromosome number is x = 17.

Systematics

The genus Vernonia was established by the German botanist Johann Christian Daniel von Schreber in 1791 in Genera Plantarum , 2, p. 541. The species previously named Serratula noveboracensis L. became the type species Vernonia noveboracensis (L.) Michx in André Michaux : Flora Boreali-Americana , 2, 1803, p. 95 . The genus name Vernonia honors the English botanist William Vernon . Since the publication by Harold Ernest Robinson in 1999, the genus only contains about 20 species, and in 2011 two species were spun off. From what used to be a very species-rich genus, many species have been separated into other, sometimes new, genera, for example into the genera Baccharoides , Gymnanthemum , Lepidaploa , Nothovernonia and Vernonella .

Of the only approximately 20 new world species, 17 species occur in North America and Mexico:

Vernonia acaulis ( Walter ) Gleason : It occurs in the US states of Florida , Georgia , North Carolina and South Carolina .
Arkansas asterisk ( Vernonia arkansana DC. ): It originates from southern North America and is cultivated as an ornamental plant in the temperate areas.
Vernonia angustifolia Michx. : It occurs in the US states of Alabama , Florida, Georgia, Louisiana , Mississippi , North Carolina and South Carolina.
Vernonia baldwinii Torr. : It occurs in the United States.
Vernonia blodgettii Small : It occurs in Florida and the Bahamas .
Vernonia fasciculata Michx. : It occurs in Manitoba , Kentucky, and the northern United States.
Vernonia flaccidifolia Small : It is found in the US states of Alabama, Georgia and Tennessee .
Hohe Scheinaster ( Vernonia gigantea ( Walter ) Trel. Ex Branner & Coville , Syn .: Vernonia altissima Nuttall )
Vernonia glauca ( L. ) Willd. : It occurs in the eastern United States.
Vernonia larseniae B.L.King & SBJones : It occurs in Texas and the Mexican state of Coahuila .
Vernonia lettermannii Engelm. ex A.Gray : It occurs in Arkansas and Oklahoma .
Vernonia lindheimeri A. Gray & Engelm. : It occurs in Arkansas, Texas and the Mexican state of Coahuila.
Vernonia marginata (Torr.) Raf. : It occurs in Kansas, Oklahoma, Colorado, New Mexico, Texas and the Mexican state of Coahuila.
Vernonia missurica Raf. : It occurs in the eastern United States, Texas, and Illinois , Iowa , Kansas , Missouri, and Oklahoma .
New York asterisk ( Vernonia noveboracensis ( L. ) Michx. ): It is widespread on the North American mainland.
Vernonia pulchella Small : It is found in Georgia and South Carolina.
Vernonia Sechellensis Baker : It was endemic to the Seychelles island of Mahé. It has not been collected since 1874.
Vernonia texana ( A.Gray ) Small : Found in Arkansas, Louisiana , Mississippi, Oklahoma, and Texas.

photos

Tufted false asters ( Vernonia fasciculata ):

Habit, leaves and inflorescences
Fruit heads

swell

John L. Strother: Vernonia Schreber. , P. 206: - the same text online as the printed work , In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico. Volume 19: Magnoliophyta: Asteridae, part 6: Asteraceae, part 1 (Mutisieae – Anthemideae) , Oxford University Press, New York and Oxford, 2006, ISBN 0-19-530563-9 . (Sections Description and Systematics)
Harold Robinson: Generic and subtribal classification of American Vernonieae. In: Smithsonian Contributions to Botany , Volume 89, 1999, pp. 1-116.

Individual evidence

↑ Harold Robinson: Generic and subtribal classification of American Vernonieae. In: Smithsonian Contributions to Botany , Volume 89, 1999, pp. 1-116.
↑ ^a ^b ^c ^d ^e ^f ^g John L. Strother: Vernonia Schreber. , P. 206: - the same text online as the printed work , In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico. Volume 19: Magnoliophyta: Asteridae, part 6: Asteraceae, part 1 (Mutisieae – Anthemideae) , Oxford University Press, New York and Oxford, 2006, ISBN 0-19-530563-9 .
↑ ^a ^b ^c ^d ^e ^f ^g ^h Vernonia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved April 16, 2018.

Web links

Commons : Scheinastern ( Vernonia ) - Collection of images, videos and audio files

Map with all linked sites: OSM | WikiMap

[Robinson1999-1] Harold Robinson: Generic and subtribal classification of American Vernonieae. In: Smithsonian Contributions to Botany , Volume 89, 1999, pp. 1-116.

[FoNA-2] ↑ ^a ^b ^c ^d ^e ^f ^g John L. Strother: Vernonia Schreber. , P. 206: - the same text online as the printed work , In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico. Volume 19: Magnoliophyta: Asteridae, part 6: Asteraceae, part 1 (Mutisieae – Anthemideae) , Oxford University Press, New York and Oxford, 2006, ISBN 0-19-530563-9 .

[GRIN-3] ↑ ^a ^b ^c ^d ^e ^f ^g ^h Vernonia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved April 16, 2018.