Estimating Yield, What Method is Best?
Every year about this time we start on our great quest to estimate yields for different fields and hybrids. These yield estimates can be helpful for planning field order, storage options, marketing decisions, and most importantly, bragging rights. While in a few short weeks, we will know our exact yields, its always nice to get an idea ahead of time where different hybrids are sitting. There area few different methods for arriving at yield estimates, and we want to talk about those today.
The Component Method
The component method is probably the most commonly used method for estimating yields. It doesn’t require any weights, but rather just kernel counts and a standardized kernels per bushel. Additionally, you want a count of your ears in 1/1000th of an acre to determine your average ears per acre. Using these components you would calculate yield like the following example.
Average Kernels counter per ear: 696
Ears per acre: 33,000
Standardized kernels per bushel: 90,000 **
**Important to note that this number will change depending on the hybrid and growing season. We use 90,000 as an average, but it could fall anywhere in the range of 60-120k.
Again, this is a pretty standard way to estimate yield. The downfall is assuming the set value of 90,000 kernels per bushel, so if you can make a more educated estimate of kernels per bushel based on knowledge of the hybrid and growing season conditions, this will make a much more accurate estimate.
This method for estimating yield is more accurate than ear counts because we are considering the actual grain weight of the particular ears. However, we still have to account for the weight of the cob to weight of the total ear. This adjustment is grain moisture multiplied by 1.411, then add 46.2. Our same ears our same ears from the first example have been drying for a while and are around 16% moisture. This means our adjustment factor is (16 x 1.411) + 46.2= 68.776. We now factor that into the entire equation.
Average Ear Weight: 8.63 oz or 0.539 lbs
Ears per 1/1000 of an acre: 33
Results of the weight method are fairly similar to the component method in this case. We have one more method that we think you are going to want to check out though.
Yield Estimator from Pioneer
If you want the quickest calculation that allows you to check many more ears in many more spots, this is the app for you. (We love using it!) It uses a similar calculation to the component method. Using imaging algorithms, the app counts the kernels per ear. (Much faster than I can, I must say!) You need to take images of at least 3 ears for a yield estimation, but more ears will give better results. Here are the images and kernel counts from my three ears:
Next, simply change your parameters to the correct stand count, growth stage, and kernels/bu to see an updated estimated yield range as well as average yield.
The benefit of the app is the ability to check multiple ears in multiple locations across your fields very quickly. This is a great benefit, particularly when we feel we might have some crop variability across fields and want to get a better picture of the yield potential across multiple productivity zones.
Some things to consider…
These are just estimates. No method is perfect at estimating yields. They each have their downfall. Our best yield measurement will be at harvest with a well calibrated yield monitor. And on that note, its time to calibrate your yield monitors. Check out our blog from 2018 covering the steps you need to take to get the most accurate yield readings, and why it matters!