FP Harvest, Pulse Beat

Combine Cleanout: How to reduce the risk of soybeans in your field peas

Dennis Lange, Industry Development Specialist – Pulses, Manitoba Agriculture

Soybeans are hard to clean out of peas. How many do you see in the above photo?

Answer at the end of the article.

COMBINE CLEANOUT CAN be a time-consuming endeavour. It is a necessity in today’s world with food allergens, herbicide-resistance weeds and other potential pests such as soybean cyst nematode. It has been stated by multiple sources that there is roughly 150 lbs of plant bio-material found inside and outside of the combine after harvest.

All this material can be a source of contamination if soybeans were the last crop harvested. Soybean growers who also grow peas have an added challenge since soybeans are one of the last crops harvested for the year and peas are the first crop harvested the following year. This doesn’t always allow for farmers to run another crop through the combine to help flush out any unwanted soybeans in the sample. This article will address a few key points on combine cleanout.

Combine cleanout should start in the fall before you leave the field and once you have finished harvesting your soybeans. Doing this cleanout in the fall allows you start the following year with a clean machine for your peas.

The goal of the in-field cleaning is to remove any material that is loosely hanging on or inside the machine. The use of a gas-powered leaf blower or portable air compressor can be used to accomplish this task. Before starting this task, open up all trapdoors including the clean grain, tailings elevator, stone trap and unloading auger sump. Next, run your unloading auger empty for approximately two minutes to clean out any beans that could be lingering in the auger. Now, run the combine with the sieves wide open and with the wind turned up for approximately two minutes. It’s also a good idea to open and close the sieves electronically to help loosen anything stuck in the sieves. You can also drive the combine over slightly rough ground to loosen any material inside the combine while running the combine.

Once that step is complete, shut down the machine and clean the flexheader. Remove any shields before starting the cleaning procedure. Use the leaf blower or compressed air to blow off any soil or debris that may be on the header including cleaning of the knife. After that is complete, remove the header and then move to the feeder house. Blow out any material that is inside the feeder house and pay attention to the corners. Finally, do a walk around the machine blowing off any unwanted material. Upon completion of this step, shut down the machine, close up the trap doors and reinstall any shields before heading home for the second and more thorough cleaning.

When you clean the combine you should start from the front and top of the combine, moving down and towards the back. This will keep the clean areas clean. Before starting the cleaning procedure open all the trapdoors and shields. This will help you access any areas where plant bio-material can be found. When you are back at the yard, start cleaning at the header. Clean off any material still adhering to the knife guards and any material still hanging on the header. After you’re done, remove the header and then move to the feeder house.

The feeder house (Figure 1) can be a major source of material contamination. Once the feeder house is clean, move to the stone trap and blow out any material that is hanging in there, paying particular attention to any corners where material can adhere to the combine (Figure 2).

Now it’s time to move to the top of the combine and grain tank. When cleaning the grain tank you should always blow the material towards the unload sump. Pay close attention to areas of the hopper such as the auger and areas behind the auger where material can accumulate (Figure 3).

Before you move down to the threshing area, blow off the top of the cab. The threshing area, concave and rotor/cylinder, can be key points where plant material can accumulate. Blowing out plant material can be a bit time- consuming but is well worth the effort in order to reduce the risk of contamination of soybeans in your peas (Figure 4).

Pay attention to any horizontal augers and the clean grain, and return elevators. Finally, inspect and clean the sieves (Figure 5).

One area that can be challenging to clean out is the unloading auger. If your unloading auger has a screen installed, remove it to gain better access. If this is not an option, another alternative is to use wood shavings packed into the unload sump and then running the auger to help to flush out any soybeans still in the auger. This should be done once the hopper has been cleaned of soybeans. The bulkiness of the material will help to move the soybeans through the auger. A bag of wood shavings is about 9 cu. ft. before compression, and can be purchased at most feed supply stores for $6–8 per bag.

In summary, a thorough combine cleanout starts in the fall when soybean harvest is completed and before the combine leaves the field. Do your initial cleanout in the field to remove all loose material on the outside of the combine. Open all doors and traps, run the machine empty for two minutes with lots of wind and run the unload auger empty to remove as many of the beans as you can before doing your cleanout out back at the yard.

Once you are back at the yard, start from the front and then move to top of combine and then down and out the back of the combine. That way cleaned areas will remain clean. Use a gas- powered leaf blower and/or compressed air to clean out the machine. Finally, clean out the unload auger by packing wood shavings in the unload sump and running the auger to flush out any of the last of the soybeans. If you have the ability to harvest a crop such as wheat, oats or barley before doing peas that will also help in flushing out any soybeans that may be left in the combine. Doing these steps will help you to reduce the chance of soybeans ending up in your harvested pea sample and both you and your buyer will be happy.

Answer: There are seven soybeans in the pea sample.