It is that time of year again! Combines are heading to the field to begin harvest after a season of praying for rain and then praying for heat. It’s shaping up to look like a good harvest in southern MN, so it’s important to make sure you are capturing good data from your monitors. I always say, “Garbage in, Garbage out” when it comes to yield data. The most important factor in valuable harvest data is calibration. Your yield monitors and scaled grain carts need to be calibrated to bring in beneficial data to your operation.
Let’s start with grain cart scales. It’s important to make sure your cart’s scale is zeroing out when empty. An effective pre-season check if you have the equipment available, is to lift a known weight into the cart and make sure your scale reads it. A good tool would be tractor weights bolted together and lifted into the cart with a forklift. After your cart is weighing accurately, start calibrating the loads from the combine. To ensure precise scale accuracy, compare the first couple of loads with your grain truck by going over a certified scale.
On a typical yield monitor, there will be a menu to assist you through calibrating the yield monitor. It is important to run these calibrations in an open part of the field. Do not calibrate when you are picking headlands or doing a lot of stopping and starting. Most yield monitors will tell you how much grain to pick for a calibration load. Unload each calibration load at a stop rather than unloading on the go. It is very important to not unload on the go, as this will introduce weighing errors.
After each calibration load, save that load and add it to the calibration curve. It is important to start each calibration load with an empty grain tank. You should take calibration loads at three speeds: normal harvest speed, ½ mph slower than normal, and ½ mph faster than normal. This is to account for different grain flow volumes. After a few calibration loads your combine scale and grain cart scale should be within a percentage point or two of each other.
Following these simple guidelines and tips should help you calibrate your yield monitor. This will allow you to record accurate harvest data for your farm operation. After you download your yield maps from the combine, make sure to have a trusted consultant help clean and analyze your data.
Have a safe and happy harvest.