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Sunflowers get their name because they always face the sun -- turning their flowers to track the sun's movement across the sky -- a phenomenon known as heliotropism. There are two types of sunflower grown -- oilseed, which are processed for their oil, and nonoilseed, used for eating and cooking. Oilseed hybrids are usually black and have a thin hull that adheres to the kernel. These varieties contain from 38% to 50% oil and about 20 percent protein. Oil is extracted by first employing a cold press method, followed by a hot press procedure. The cold-press oil is used as a food and cooking oil, while the hot-press oil is used mainly in industry, in such products as lubricants, soap, paint and varnish. The sunflower meal, called "press cake," is used as a high protein feed for livestock. The kernels of nonoilseed sunflower are eaten, raw or roasted, by humans, used to make flour and are a prime ingredient in many feeds for both wild and domesticated birds. The flower petals can be used to create a natural yellow dye. The crop stubble can be grazed and the hulls left over after processing are used as filler in livestock feeds. |
| Sunflower is a North American native, first utilized and cultivated by Native Americans. Of all the world's seed crops, it is the only one domesticated in North America. American Indians used sunflower as food and medicine, a source of dye and oil, and as a hunting indicator. When sunflower was tall and in bloom, it meant that the buffalo were fat and their meat good. Spanish, English and French explorers collected sunflower, and by the 1600's, it was a common garden flower in Europe, from whence it spread along the trade routes throughout Africa and Asia. Sunflower is the state flower of Kansas and grows wild throughout North America. Unlike most domesticated crops, the wild form of the cultivated sunflower is still found in abundance, growing as a weed. Wild sunflower is highly branched with small heads and small seeds, in contrast to the single-stem and large seed head of domesticated sunflower. The cultivated sunflower (Helianthus annuus L.) is one of 67 species in the genus Helianthus. Jerusalem artichoke (H. tuberosus L.), is grown for food and feed, a few species are grown as ornamentals, and the rest are weeds. Plant breeders have made interspecific crosses within the genus Helianthus and have transferred characteristics such as higher oil percentage, cytoplasmic male sterility, and disease and insect resistance to the commercial plant. | |
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Many disease-causing fungi and bacteria are associated with sunflower, but, fortunately, only a few are of economic significance, as long as a strict crop rotation is followed. However, some of the biggest pests sunflower producers face are birds. Seeds are exposed and the large head serves as a perch during feeding. As a result, a number of control measures have been devised to handle the feathered pests. Access trails are left in large fields to aid in scaring birds from the center of the field. Weeds have to be kept in check because they are often a food source before the crop matures. Crop stubble is left standing, and lure crops are planted to attract birds away from unharvested fields. Numerous methods are employed to frighten the birds away from the sunflowers, including cannons that automatically detonate a gas to produce loud explosions. These devices range from relatively simple to deluxe models with photoelectric regulators and programmable firing sequences. Speakers that broadcast bird distress calls are used in the smaller fields. Low-flying planes are used to chase flocks from sunflower fields, an effective technique when combined with other methods, such as pyrotechnic devices. Finally, bird-resistant hybrids are becoming more popular, as they are developed. The seed of these hybrids is protected by morphological traits, such as concave-shaped heads, horizontally-oriented heads, and long head-to-stem distance, making it hard for birds to get at the seed. |
| Sunflower was developed first as an important commercial oilseed crop in the Former Soviet Union (FSU). Major producers are the FSU, Argentina, USA, China, France, and Spain. The large sunflower seed allows for deep seeding in dry conditions. It has a highly efficient root system, so it can utilize nitrogen and moisture from lower soil levels and thus can be grown in areas which are too dry for many crops. Plants are quite drought-resistant except during flowering. One reason that sunflower is grown so widely is its relatively short growing season, generally requiring 90 to 100 days from planting to maturity. The crop may be grown on a wide range of soils, including poor soils, provided they are deep and well-drained, but the plants don't like acidic or waterlogged soils. The high stalks remaining after harvest make excellent snow traps. Sunflower oil has been researched as a potential diesel fuel substitute. Most modern varieties are autogamous, able to produce seed without help from insect pollinators. | |
Links to sites with more information about sunflower:
| Crop Plant Resources | | Outreach
and Educational Resources | | Molecular
Biology Program |
Please send comments and suggestions to: moconnel@nmsu.edu
Last Updated: June 8, 1999
