SD No. 1 in sunflower productionIn 2013, South Dakotans planted 617,000 acres of sunflowers. No other state came close to this number of acres. North Dakota was second, planting fewer than 500,000 acres of sunflowers in 2013. Sunflowers have been a successful and profitable crop for many South Dakota farmers.
By: SDSU Extension Service ,
BROOKINGS, S.D. — In 2013, South Dakotans planted 617,000 acres of sunflowers. No other state came close to this number of acres. North Dakota was second, planting fewer than 500,000 acres of sunflowers in 2013. Sunflowers have been a successful and profitable crop for many South Dakota farmers.
“In 2011, gross sales or receipts for sunflowers in the state totaled $192 million,” says Ruth Beck, South Dakota State University Extension agronomy field specialist.
Beck explains that there are two types of sunflowers planted in South Dakota: oilseed types used for birdseed or crushed to make sunflower oil and confection types or those grown for human food markets.
She adds that seeds of the two types are easily differentiated. The oilseed type has small black seed and a thin hull or shell that adheres to the kernel. The confection or nonoil seed types have a thicker, larger, hull and a larger seed that is easily separated from the hull. The shells are usually a lighter shade and have some white striping. Typically, the confection plants produce seed that has lower oil percentage and test weight.
“Oilseed types are the most popular in South Dakota, being grown on about 86 percent of acres in 2013. They average around 42 percent oil content and are marketed into the oil and the birdseed markets,” Beck says.
As with any crop, variety selection is a very important part of production.
“Sunflower varieties are hybrids and are therefore purchased each year from commercial seed companies,” Beck says.
When selecting hybrids, Beck encourages selection to reflect desirable yields. High oil percentage for oil types, proper maturity, proper seed size for confection types, insect tolerance, and disease resistance. Standability and head position after flowering are also selection criteria.
Sunflower varieties are tested annually in South Dakota by SDSU.
Although sunflowers are classified as intermediate in water use efficiency, Beck explains that they are often considered drought tolerant because they have a deep tap root.
“This allows them to extract water from deep in the soil profile and also enables them to use nitrogen and other nutrients that leach below the root zone of shallow-rooted crops,” she says.
Because of this, she adds that careful consideration should be given to the type of crop that follows sunflowers, in part, because their ability to scavenge water and nutrients can affect following crops.
Sunflowers are produced primarily in the central and western region of South Dakota under no-till crop production systems. No-till systems rely heavily on diverse crop rotations, Beck explains.
“Sunflowers should be planted in a diverse rotation in order to minimize issues with disease, weeds and insects. Since sunflowers are native to this area, risks from diseases are magnified by short sequencing of sunflowers in a crop rotation,” she says.
Sunflowers are commonly planted in rows that range from 20 to 36 inches using corn planters. But they are sometimes seeded in narrower rows using a small grain drill or air seeder.
Beck says this seeding method is less than ideal because both depth control and seed singulation capabilities of these seeders is not as good as with row-crop planters.
“Sunflowers are very sensitive to variation in plant spacing and planting depth uniformity. There is no advantage to going narrower than 15-inch spacing,” she says.
She explains further that if the producer was using a population of 27,000 plants per acre, 30-inch rows would place a seed every 7.5 inches; 20-inch rows have a seed spacing of 11.6 inches; 15-inch rows give seed spacing of 15.5 inches. Planting in 10-inch rows gives a seed spacing of more than 23 inches within the row. Plant population of 22,000 to 27,000 plants per acre are common for oilseed types. Confection sunflowers are planted at lower plant populations than oilseed sunflowers, as they need to attain large seed size.
It is a common IPM practice in South Dakota to plant sunflowers in mid- to late June. Beck says this can reduce insect and weed pressure and spread work load for farmers. It may also improve stand uniformity.
“Oil is the last thing that a sunflower plant produces, therefore, late planted fields are dependent on moisture late in the season to improve their oil content,” she says.