Many grain producers from the Prairies are about to run soybeans through their combines for the first time. There was a 40 percent increase of Manitoba soybean acreage over last year and a 250 percent increase of the crop on Saskatchewan fields.
Soybeans are relatively easy to separate, although there are a few things growers should keep in mind when the soybeans are ready to come in.
Harvey Chorney researches harvest losses for the Prairie Agriculture Machinery Institute (PAMI) and he’s also grown soybeans for 15 years on his farm near East Selkirk, Man.
He said soybeans are easy to combine because of the large difference between the size of the soybeans and the rest of the plant residue.
“You get good thrashing ability and the separation at the shoe is really easy to set up. It’s not that difficult to set up with the settings that are recommended from the combine manufacturers. It’s one of the easy ones,” Chorney said.
“Any farmers comfortable setting up a combine for canola I would believe would have no trouble setting it up for beans.”
He said operators will need to reduce the speed of the rotor, yet they still have to run a fairly tight concave adjustment to make sure all of the beans are removed from the pods.
“You don’t want to end up with a bunch of pods in the tank. But you can’t be too tight because you can start crushing beans.”
Chorney said he would be more concerned with having pods in the grain sample then a few crushed beans, because dockage will be worse with the pods.
Operators new to harvesting soybeans have to keep in mind the crop requires approximately half of the load a combine’s threshing system is capable of handling, far less then other crops such as cereals, he said.
“The way we grow soybeans in Canada, there is no way you are going to load your combine. The tendency is that if you were used to running grain crops through it and hearing the engine loading, you’re going to be exceeding the speed of your header if you try to push it that far,” Chorney said.
With the soybean varieties grown on the Prairies the first pods formed are just above the ground, and they have the plumpest kernels that growers definitely do not want to leave behind.
As much as 80 percent of soybean harvest losses occur at the header, which is why PAMI is running harvest trials that examine how ground speed and a header equipped with an air reel effect losses.
Lorne Grieger of PAMI said harvest losses can be around 10 to 15 percent of total yield right at the header, and it’s very easy to go too fast and miss the bottom pods.
“Our research was looking at how do you manage that harvest condition with your header and ground speed in order to maximize your yield at the end,” Grieger said.
The study examined four harvest speeds two, three, four and five miles per hour) and two auger headers were used. The difference between the straight-cut headers is that one was equipped with an air reel system.
“We looked at an air reel or air knife system where you blow air across the cutter bar and try to blow any seeds that were cut but not necessarily captured back into the header and eventually through into the grain tank,” Grieger said.
He said adding an air reel can significantly reduce losses.
The overall difference between the two headers was 1.25 bushels per acre, with the air reel having reduced losses across all speed treatments by about 55 percent.
Harvest speed has a significant effect on header losses beginning at around five miles per hour.
The slower speed treatments of two, three, and four m.p.h. had about .69 bu. per acre losses and there were little differences be-tween these slower treatments.
But once speed was increased to five m.p.h. a .85 bu. per acre loss was observed, up nearly 40 percent from the slower speed treatments.
Grieger said it is clear that cutting is the limitation when it comes to soybean harvest and that slowing down and cutting as low to the ground as possible can make a major difference in terms of harvest losses.
Soybeans can be harvested at moisture levels of 20 percent or less, but must be stored at 14 percent moisture or lower.
The optimum harvest moisture range for soybeans is 13 to 15 percent to achieve minimum field losses and maximum weight.
Harvesting below 12 percent moisture content can increase damage to the soybeans and shattering losses.
Chorney said moisture content of beans varies throughout the day so some growers start early in the morning, 10 a.m. to 11 a.m., when the beans are a little bit damp. This enables growers to blend the early morning harvested soybeans with afternoon harvested soybeans that can be drier than they need to be.
Harvest tips from Producer readers
We asked growers on Facebook for soybean harvesting tips, and here are a few of the responses:
Kory Pick of Macoun, Sask., has grown beans for four years and he loves them. He said they are easy to harvest, stand well and will sit and wait until you’re ready to harvest.
“They don’t downgrade like peas, etc. So you can leave them till last and do more grade sensitive crops like durum or lentils and peas. The aerate well, so if it’s hot and dry out you can take them a little tough and fan them down. If it’s tough harvest conditions the pods can get “rubbery” and will not thresh out well. Wait for some sun. Cracks and splits are not dockage. Don’t be too worried when you see that in your sample.”
Christian A. Herrnböck of St. Gregor, Sask., said growers need to be patient and wait for soybeans to adequately dry down.
“Don’t put green stems through or you’ll be plugging. They combine great in December too,” Herrnböck said. “They go through like nothing and not as fragile as a pea, set the combine like you would for peas. They don’t need desiccation and once the leaves are off and the stems are reasonably
brown they are good to take off.”
He also said soybeans do not lose moisture like peas under aeration, they aerate similar to how canola does because they lose moisture slowly.
Christopher Thorson from Penzance, Sask., said he had success aerating his soybean crop last year.
“I blew air at 10000 bu. last year and brought them down two points, no problem.”