Proper equipment set-up is important when it’s time to harvest, says Trygg Olson, a Field Sales Leader for Nuseed.
“Make sure the fan is set at the right speed. If it’s too high, you’re blowing too much out the back. If the fan speed is too low, you’re going to have empties, which will affect the test weight,” he says. “If you’re too fast on the rotor, or if the concaves are set too tight or too loose, you’re going to have trash in there and you’ll start grinding the seed up and shelling seeds out.”
The target for seeds thrown behind the combine is less than 10 seeds per square foot, which is 100 pounds of actual yield, says Jed Wall, sunflower business development manager for Legend Seeds in Wahpeton, N.D.
Wall also emphasizes the importance of test weight and encourages growers to check they’re getting their desired test weight when harvesting.
“When you’re combining, always play with your air and don’t be afraid to blow your empties out of the back. With sunflowers we’re always going to have some blanks. Blank seeds sometimes get mistaken for actual pounds—the more blanks, the lower the test weight is. If the test weight is too low, you’re going to have a hard time selling product,” he says.
“Growers are sometimes afraid to turn up the air and they don’t check their test weights as they go. At the point of selling, those sunflowers weigh 26 pounds per bushel. If you break the sample down, some seeds didn’t fill because they were deformed, or there’s empty hulls,” says Wall.
Ground speed is also important. Olson recommends a ground speed that keeps the combine full so that it’ll do a good job of threshing: this may be somewhere between three and five miles per hour. However, today’s large combines often need to travel more than five miles per hour to keep full.
Combines used for threshing small grains can be adapted to harvest sunflowers. Platform and corn headers can be used with some modifications, such as catch pans, a deflector bar and a small reel. A rotating drum can be used to replace the deflector bar and reel. A row-crop header can be used without modifications.
However, a header designed for sunflowers is worth the investment, says Olson. “A sunflower designed head is going to pay for itself because it will greatly reduce shatter loss and do a better job of harvesting.”
Keeping a clean combine at harvest is essential as it decreases fire risk. Growers should blow the combine down at least twice per day and have extinguishers on hand, says Wall. A snorkel system, which is an extension for the air intake on a combine, is also available for fire risk mitigation.
One last qualification for harvesting success is a good attitude, not a “good enough” attitude. “Some growers run into trouble with a good enough attitude. They’ll tell themselves things look good enough and they’re either blowing too much out of the machine or they’re not blowing enough. They end up with a big expensive recleaning or going to a less desirable market,” says Wall.
“Make sure the product you’re putting in the bin is a good quality product and makes the specs for what you’re going to sell it for,” he says.