common sunflower (Maricopa Native Seed Library)

common sunflower

Helianthus annuus

Summary ⁵

Helianthus annuus, the common sunflower, is a large annual forb of the genus Helianthus grown as a crop for its edible oil and edible fruits (sunflower seeds). This sunflower species is also used as bird food, as livestock forage (as a meal or a silage plant), and in some industrial applications. The plant was first domesticated in the Americas. Wild Helianthus annuus is a widely branched annual plant with many flower heads. The domestic sunflower, however,...

Description ⁶

The plant has an erect rough-hairy stem, reaching typical heights of 3 metres (9.8 ft). The tallest sunflower on record achieved 9.17 metres (30.1 ft). Sunflower leaves are broad, coarsely toothed, rough and mostly alternate. What is often called the "flower" of the sunflower is actually a "flower head" or pseudanthium of numerous small individual five-petaled flowers ("florets"). The outer flowers, which resemble petals, are called ray flowers. Each "petal" consists of a ligule composed of fused petals of an asymmetrical ray flower. They are sexually sterile and may be yellow, red, orange, or other colors. The flowers in the center of the head are called disk flowers. These mature into fruit (sunflower "seeds"). The disk flowers are arranged spirally. Generally, each floret is oriented toward the next by approximately the golden angle, 137.5°, producing a pattern of interconnecting spirals, where the number of left spirals and the number of right spirals are successive Fibonacci numbers. Typically, there are 34 spirals in one direction and 55 in the other; however, in a very large sunflower head there could be 89 in one direction and 144 in the other. This pattern produces the most efficient packing of seeds mathematically possible within the flower head.

Most cultivars of sunflower are variants of Helianthus annuus, but four other species (all perennials) are also domesticated. This includes H. tuberosus, the Jerusalem artichoke, which produces edible tubers.

History ⁶

This species was one of several plants cultivated by Native Americans in prehistoric North America as part of the Eastern Agricultural Complex. Although it was commonly accepted that the sunflower was first domesticated in what is now the southeastern US, roughly 5000 years ago, there is evidence that it was first domesticated in Mexico around 2600 BC. These crops were found in Tabasco, Mexico at the San Andres dig site. The earliest known examples in the United States of a fully domesticated sunflower have been found in Tennessee, and date to around 2300 BC. Other very early examples come from rockshelter sites in Eastern Kentucky. Many indigenous American peoples used the sunflower as the symbol of their solar deity, including the Aztecs and the Otomi of Mexico and the Incas in South America. In 1510 early Spanish explorers encountered the sunflower in the Americas and carried its seeds back to Europe. Of the four plants known to have been domesticated in eastern North America and to have become important agricultural commodities, the sunflower is currently the most economically important.

During the 18th century, the use of sunflower oil became very popular in Russia, particularly with members of the Russian Orthodox Church, because sunflower oil was one of the few oils that was allowed during Lent, according to some fasting traditions. In the early 19th century it was first commercialized in the village of Alexeyevka in Voronezh Governorate by the merchant named Daniil Bokaryov, who developed a technology suitable for its large-scale extraction, and quickly spread around. The town's coat of arms includes an image of a sunflower ever since.

During the 19th century, it was believed that nearby plants of the species would protect a home from malaria.

Among the Zuni people, the fresh or dried root is chewed by the medicine man before sucking venom from a snakebite and applying a poultice to the wound. This compound poultice of the root is applied with much ceremony to rattlesnake bites. Blossoms are also used ceremonially for anthropic worship.

Fontes e Créditos

(c) Andreas Rockstein, alguns direitos reservados (CC BY-SA), https://www.flickr.com/photos/74738817@N07/28686316360/
(c) Ken-ichi Ueda, alguns direitos reservados (CC BY), uploaded by Ken-ichi Ueda
(c) Tony Iwane, alguns direitos reservados (CC BY-NC), uploaded by Tony Iwane
(c) Kim, Hyun-tae, alguns direitos reservados (CC BY), uploaded by Kim, Hyun-tae
Adaptado por Jeny Davis de uma obra de (c) Wikipedia, alguns direitos reservados (CC BY-SA), https://en.wikipedia.org/wiki/Helianthus_annuus
(c) Wikipedia, alguns direitos reservados (CC BY-SA), https://en.wikipedia.org/wiki/Helianthus_annuus

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