The key to a successful soybean harvest is preparation and anticipating problems, say Extension specialists.
Here are several soybean and machinery experts’ tips to help you head into harvest with the fewest headaches, breakdowns and delays:
1. Inspect machinery in advance. “Know the recommended combine and cylinder settings,” advises Mike Staton, Michigan State University Extension educator for Allegan County and Soybean 2010 project coordinator. “Have the equipment well maintained and ready to go by harvest.”
Inspect machinery for potential problems before heading into the field, agrees Mark Hanna, Iowa State University Extension ag engineer. “Inspect belts and chains for proper tension, check auger flighting wear and look at wear on rasp bars and the cylinder or rotor concave,” he says. “Also, check the cleaning shoe for broken or bent sieves.”
The cutter bar should undergo the most scrutiny, advises Hanna. “For soybeans, 85-90% of total machine losses tend to be at the head,” he says. “Of these head losses, probably 80% occur at the cutter bar. Check the cutter bar for wear and flex and height-control adjustments to help assure more beans are harvested.”
Ensure all knives are sharp and that knife guards are tight and in good condition.
2. Scout fields before harvest. “Pre-scout your fields by mid-August for weed issues,” advises Hanna. “Know what to expect.”
Viny weeds like morning glory and burcucumber can create difficult challenges at soybean harvest, says Vince Davis, University of Illinois Extension soybean agronomist. “If fields have viny weeds, you might have to wait until they dry down to harvest; or spray bad patches,” he says.
Green stem – stems that stay green after leaf drop – can also complicate harvest, adds Davis. “Green stem is difficult to predict from year to year,” he says. “In some cases, it can take a frost to kill green stems and allow for harvest. Usually it’s related to having few or no pods on the plant. Don’t let just a few pockets of green stem delay harvest for the rest of a field.”
3.Carefully monitor moisture content to stop shatter losses, emphasizes Staton. “The biggest mistake with soybean harvest is poor timing,” he says. “Harvest fields sooner rather than later to avoid the repeated drying and rewetting cycles that can increase shatter losses once moisture levels initially drop below 13%.”
Moisture content will change from field to field, depending on planting dates, variety maturity and time of day, says Staton. “Try to time your initial harvest right around 15% moisture content,” he advises. “As you move from one field to another, recheck the moisture content and adjust your combine settings. Moisture levels change more rapidly in soybeans than they do in corn.
“Once soybeans dip below 11% moisture, you’ll have problems with shattering,” he says. “One solution is to wait to harvest until evening, when humidity levels increase. When moisture levels are above 15%, then soybeans are too wet to combine.”
4. Get low, stay low. Lodged or stunted beans can present a challenge at harvest, says Orvin Bontrager, Servi-Tech, Inc., Aurora, NE. “Get the reel or soybean head down low enough so that you’re not missing any pods.”
Strive to keep bean harvest losses from machinery and operator error at about 1 bu./acre or less, says Hanna. “The average machinery loss during soybean harvest in a good year in the Midwest is about 1.5 bu./acre,” he adds. “However, for every inch that you cut too high, you lose about 1 bu./acre. It’s also common for combine operators who have not properly adjusted machinery settings to lose 2-5 bu./acre or more.”
If the crop is standing well, Hanna advises setting the reel index (ratio between reel speed and ground speed) for the bat and finger pickup somewhere between 1.25 and 1.50 (25% faster or 50% faster than ground speed). If the crop is lodged, he recommends increasing the reel index to 1.50-2.00.
5. Adjust on-the-go. Check your grain tanks periodically for unthreshed pods and split or damaged beans and adjust concave and cylinder settings on-the-go as necessary, says Staton. “Also, check the ground behind the combine for unthreshed pods or for shelled beans left on the ground and adjust the blower and sieve settings if necessary,” he adds.
6. Consider corn first. “Farmers who planted corn early and soybeans late may harvest some corn first before finishing soybean harvest,” says Robert Hansen, Ohio State University Extension ag engineer. “That way you won’t hold up corn harvest while you’re waiting for soybeans to dry down.”
Farmers who want to receive the best price by weight can also blend loads of high- and low-moisture soybeans before delivering to the elevator to achieve an average 13% moisture level, says Hansen. “If you deliver beans at 11% rather than 13%, you’ll deliver less water to the elevator than you’re allowed to, and you’ll sacrifice up to $200/1,000-bu. load,” he says. “Higher-moisture soybeans can be dried quickly in a storage bin with natural air (0.5-1.0 cfm/bu.) to avoid reduced quality.”
7. Screen your beans. “If you’re storing soybeans for future delivery in March or April, screen them prior to loading them into the bin,” says Hansen. “Pods that are green, weed seed and fines all contribute to an increased chance of spoilage.
“You can also unload soybeans from bins, run them through screens and reload them into bins later in the fall,” he adds.
8. Stay safe. Consider safety issues and emergency preparations before harvest, Hanna recommends.