A samara (, ) is a winged

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...

, a type of

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

in which a flattened wing of fibrous, papery tissue develops from the ovary wall. A samara is a

simple Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by John ...

dry fruit, and is

indehiscent Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that ...

(not opening along a seam). The shape of a samara enables the wind to carry the seed further away from the tree than regular seeds would go, and is thus a form of anemochory. In some cases the seed is in the centre of the wing, as in the elms (genus ''Ulmus''), the hoptree (''

Ptelea trifoliata ''Ptelea trifoliata'', commonly known as common hoptree, wafer ash, stinking ash, and skunk bush, is a species of flowering plant in the citrus family (Rutaceae). It is native plant, native to North America, where it is found in Canada, Mexico, ...

''), and the bushwillows (genus ''

Combretum ''Combretum'', the bushwillows or combretums, make up the type genus of the family Combretaceae. The genus comprises about 272 species of trees and shrubs, most of which are native to Tropics, tropical and southern Africa, about 5 to Madagascar ...

''). In other cases the seed is on one side, with the wing extending to the other side, making the seed autorotate as it falls, as in the

maple ''Acer'' is a genus of trees and shrubs commonly known as maples. The genus is placed in the soapberry family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated si ...

s (genus '' Acer'') and ash trees (genus ''

Fraxinus ''Fraxinus'' (), commonly called ash, is a genus of plants in the olive and lilac family, Oleaceae, and comprises 45–65 species of usually medium-to-large trees, most of which are deciduous trees, although some Subtropics, subtropical specie ...

''). There are also single-wing samara such as mahogany (genus

Swietenia ''Swietenia'' is a genus of trees in the Melia azedarach, chinaberry family, Meliaceae. It occurs natively in the Neotropics, from southern Florida, the Caribbean, Mexico and Central America south to Bolivia. The genus is named for Dutch-Austria ...

) which have a shape that enables fluttering. Some species that normally produce paired samaras, such as ''

Acer pseudoplatanus ''Acer pseudoplatanus'', known as the sycamore in the British Isles and as the sycamore maple in the United States, is a species of maple native to Central Europe and Western Asia. It is a large deciduous, broad-leaved tree, tolerant of wind an ...

'', can also produce them in groups of three or four. File:TripleSycamoreSamara.png, Unusual group of three samaras of sycamore maple (''

''. Normally, they are in pairs.) File:Starr_040601-0006_Fraxinus_uhdei.jpg, Seeds of the tropical ash ('' Fraxinus uhdei'') File:Ptelea_trifoliata_20050606_635_part.jpg, The hoptree (''

'') File:Ulmus-pumila-samaras.jpg, The Siberian elm ('' Ulmus pumila'')

In culture

A samara is sometimes called a ''key'' and is often referred to as a '' wingnut'', ''

helicopter A helicopter is a type of rotorcraft in which Lift (force), lift and thrust are supplied by horizontally spinning Helicopter rotor, rotors. This allows the helicopter to VTOL, take off and land vertically, to hover (helicopter), hover, and ...

'', '' whirlybird'', '' whirligig'', ''polynose'', or, in the north of England, a ''

spinning jenny The spinning jenny is a multi- spindle spinning frame, and was one of the key developments in the industrialisation of textile manufacturing during the early Industrial Revolution. It was invented in 1764–1765 by James Hargreaves in Stan ...

''. During the autumn months, they are a popular source of amusement for people that enjoy tossing them in the air and watching them spin to the ground.

In culture

References

Further reading