With harvest upon us, it’s important to talk harvest management — and how you can make sure every bean gets into the bin.
Harvest Timing #
Soybeans become fully mature at the R8 stage. By then they will have dropped their leaves and be a tan-brown colour, with the seeds rattling in each 95% brown pod. Around 10 to 14 days after that, they should be ready to harvest, weather depending.
“If you get late-season precipitation or find weeds becoming an issue, desiccating is an option,” said Justine Cornelsen, Agronomic & Regulatory Services Manager at BrettYoung.
The best time to desiccate your field is when the least mature part of it is at less than 30% moisture. Cornelsen recommends using the spray to swath calculator to ensure the maximum residue level (MRL) is not affected by the pesticide product you may be applying.
Manitoba Agriculture Pulse and Soybean Specialist, Dennis Lange, said desiccation of a soybean crop is not very common — it’s typically only done when weed pressure is high and could affect the crop’s harvestability.
“I have seen growers use it to help dry down a long-season variety quicker,” he said. “But that’s more of a variety selection issue.”
BrettYoung has a broad range of maturities within our soybean variety line-up. To view the entire portfolio, click here.
Combine Settings #
Direct combining, or straight cutting is the perfect method for harvesting your soybean crop, as with swathing, you’ll need to combine shortly after anyways to avoid seed quality loss. Lange reminds growers to use the correct concaves for soybeans, typically a wide-wire one that allows larger seed to pass through quicker.
He also recommends setting your cylinder speed range at 500 to 700 RPM, a much slower pace than one you’d use when harvesting wheat. Along with that, Lange recommends a wind speed of 850 to 900 RPM, which will allow for good separation of lighter material.
If you’re facing a year with shorter plants, Cornelsen said using an air bar with the flex header will get the soybeans pushed into the header and not left laying on the knife, which reduces harvest losses.
Measuring Losses #
When it comes to soybean crops, over 80% of harvest losses occur at the header — it only takes four seeds/ft2 to lose a bushel/acre.
Recent work through the Prairie Agricultural Machinery Institute (PAMI) looked at the variables affecting header losses like header type, the angle of the header, air systems, and ground speed. They found a draper header, when adjusted properly, allows for a smoother flow of plant material over the cutter bar, and creates less pod shatter.
PAMI also found the header angle is one of the most important settings to keep in mind. Your header’s knives should be positioned between the ground and at the lower tip of the bottom pod, helping distribute the cutting load across the entire header.
Slower ground speeds also see less losses, but you know your combine best. Knowing your machine and measuring its losses are a better indicator of which speeds you should be harvesting at. In their research, PAMI also found an air system reduces losses by 0.5 to one bushel/acre.
To calculate your losses, use Manitoba Pulse & Soybeans Growers’ tool here.
After you’ve checked your losses, it’s time to assess the number of seeds on the ground before you alter those combine settings. This will help you to determine what is and isn’t working. Lange said to count loose seeds, dropped pods, and stalks that may be lodged to get the full circle view of seeds on the ground.
To ensure no bean is left behind, change one combine setting at a time.
