As I settle back into farming after the Oshkosh Air Show last week and start to look ahead towards harvest, my little yield estimation gadget inside the AirScout platform becomes pretty handy. Back when I first started messing around with thermal imagery, I noticed that there was nearly always a thermal image during the course of the season that correlated with my yield map. In fact, I started playing a game where I would pull into the field with the combine, and then pull up the “forecast image” to see how close it would be. I was astounded by the accuracy of the patterns. Because of this, I thought of a way we could leverage this information as farmers, and the “Yield Estimator” was born. It’s really quite simple, so here are a few instructions:
1) Pick the THERMAL picture from initial canopy to present that shows the MOST VARIABILITY. (This is often from the same date as the “Fat Kids” picture, unless there is drought stress or another adverse weather event later in the growing season.)
2) After clicking on that thermal picture, hit the “Yield Estimate” tab. At this point, the computer will clip the image to the field’s boundary, and drop three pins on the image. These pins represent the hottest, coldest, and exact center temperature of the field.
3) Hit the “Save as Custom Image” tab, and now use your iPad/iPhone to walk to these three specific places (You will have to use your alignment feature – let me know if you need help with this.)
4) Do a yield check at each of these locations. You can use any method you are comfortable with, but here are a few links for corn and soybeans you might find useful:
Estimating Corn Grain Yield Prior to Harvest (Agronomy Dept, Purdue)
Estimating Soybean Yields – Simplified (Purdue Extension)
5) Now enter what you found at each location into the Yield Estimator, and hit “Calculate”. At this time, the computer will look at every pixel inside your field’s boundary and assign a yield factor based on the temperature of that pixel and the information you just provided. At the bottom of the page you will see the average yield estimate and the total number of bushels the computer expects at harvest time.
There are a few other features that allow you to erase areas you don’t want included in the calculation, or even move the pins manually. My Yield Estimator is meant to remove the ambiguity of WHERE the samples are taken, and HOW MUCH of the field is represented by that sample location. As with nearly everything, nothing is perfect, but this is certainly better than just taking a random sample wherever the pick-up truck stops rolling.
Have fun with this and let me know if you have any questions. We are constantly working on ways to improve this gadget and make it even easier to use, so your suggestions are always welcome. As a farmer, I have always said that half my job is growing the crop, but the other half is marketing that crop. By getting an early feel for how many bushels I can reasonably expect, it makes that second half much easier. Please take advantage of this important tool to improve your farm’s profitability!