The harvest is in full swing! Maybe you’ve seen some big machines out and about, and maybe you’ve noticed they don’t all look the same. You may be wondering, what’s the deal with that?
The biggest difference between modern combines (other than the color or brand) is what header they have on. Here in Iowa, our two biggest crops are corn and soybeans. Since these plants grow differently, it takes different equipment to harvest them in the fall.
Luckily, there is one master piece of equipment – the combine – that can harvest both crops. However, it needs different attachments to get the job done right. These attachments are called heads or headers. You can think of it kind of like vacuum cleaner attachments.
The corn head looks like it has long, witchy fingers – very fitting for Halloween! These fingers reach in between the rows of corn. At the base of the fingers, there are rollers that cut and pull down the stalk, and chains that break the ear of corn off the stalk. After that, augers will rotate and feed the corn into the combine machine itself.
The bean head, used to harvest soybeans, is also called a draper head. If you’re familiar with the kids’ movie Cars, this is the kind of header that Frank, the combine, has. This header has five or six bars that rotate down. On each bar, there are small, rubber fingers that help grab the plant and bring it towards the machine. You can think of this like the main roller on the bottom of your vacuum cleaner; the bars create something of a roller that grabs and pulls the plants towards the machine. Then, the plants will come across the cutter bar at the base of the header. This will cut down the plant, and then the augers will collect the plant material to take it inside the machine.
The combine doesn’t stop there, though. Once the plant is cut down and the material is inside the combine, there is still sorting to do! When crops are in the field, corn is on a cob and is surrounded by husks. Soybeans are inside of a pod. The combine has to detach these seeds from the other plant material and collect it all in one place.
All of the extra plant material will be deposited back on the field using a spreader in the back of the combine. This helps give the soil extra cover and protection from erosion, and also helps put some nutrients back into the soil from the organic matter of the plant material.
Once the grain is collected, it is temporarily stored in the grain tank of the combine. In the picture below, you can see that the tank is fairly full. When the tank looks full, another farmer will drive alongside the combine with a tractor and a grain cart. The combine will then use an auger to deposit the grain into the cart. When this happens, the combine doesn’t have to stop harvesting. Instead, the grain cart driver can go back and forth between a larger semi-truck and the combine to collect and deposit the grain. This saves lots of time!
In summary, combines do lots of work! Even though they don’t drive very fast, the amount of work one combine can do in a day is leaps and bounds more than farmers could do without them. Luckily, we have the tools and equipment to harvest our two largest Iowa crops as efficiently as we do.