Success in precision farming doesn't come overnight. A solid grasp of agronomic fundamentals is a prerequisite to success. So is patience, because the factors influencing success, especially the weather, vary from year to year. Here are some key points to ponder.
By Ken Ferrie, Farm Journal Field Agronomist
One lesson I relearn every year—whatever the growing conditions—is to respect what a field tells you. Yield data can be frustrating and difficult to interpret, especially in a year like 2012 where we saw 100-bu. swings in a single field due to severe drought. That experience was a reminder that it takes time to dig deep and fully understand why crops turn out the way they do.
Fundamentals matter. The more you know about agronomic fundamentals, the easier it is to achieve higher yields, especially the ones promised by precision agriculture. Without a firm grasp of the principles of soil, water, pest management and fertility, it’s tough to understand why something happened or to recognize the repeatability you need to make a management change. Key decisions must be rooted in the fundamentals.
Technology is a game-changer. The good news is that our plots are no longer analyzed pass by pass. We use management zones that are redefined and refined every year. As each piece of new technology comes along, it opens the door for other opportunities and technologies. We can do things now that we didn’t even dream about 20 years ago. Take the drought of 1988 as an example. Back then we knew areas of a field were dead, but we didn’t know specifically where they were. With the 2012 drought, aerial imaging and yield mapping allowed us to know definitively where they are. Even if it’s only one soil type in one management zone, we can answer the question of why it fell so hard.
Variable-rate technology has arrived. In 2012 as we investigated our results, it was apparent that water was king and we saw impressive responses to variable-rate populations. If you made decisions on just one year’s data, you’d lower all your populations because of the risk of high populations in a droughty year. Ten years ago, a lot of our fields weren’t planted thick enough and 28,000 plants per acre was a high-rate population. Today, the high population rate is up to 36,000, but our data also says some areas of the field are planted too thick. That’s where variable-rate population pays. Variable-rate nitrogen isn’t as impactful in a dry year, but nitrogen timing is still important to manage. All of this adds up to tweaking management zones every year for the best success.
The planter pass is paramount. Whether you’re planting corn, soybeans or cotton, it’s crucial to get the planter pass right and get the crop off to a strong start. There is no substitute for that. Fortunately, there is technology available today that can help us monitor planter performance and tweak it in the field.
Nitrogen demands management. The weather and environment have such a big impact on nitrogen that you can’t manage all the variables just once a year. These include rainfall, crop residue, tillage conditions, mineralization rate of soils and more. Nitrogen is a moving target, and farmers need to be ready to react. Even though nitrogen is an input we apply every year, producers should approach it as they do pests, recognizing that changes in condition require a tailored approach.
Once that mindset is in place, a farmer is ready to consider assorted application methods, various products to manage risk, technology to apply different rates in different parts of the field, and the latest technology in testing. For example, the Illinois Soil Nitrogen Test, which we use to estimate the amount of nitrogen the soil can give, is a good place to start. Overall, I’ve seen top-notch nitrogen management translate to 100-bu. increases in yield.
Uniform soil density. If you go back 25 to 30 years, we were hitting a wall with strip-till and no-till. But then we realized the problems were underground and that we have to manage for a uniform soil profile. Now we can pinpoint past density issues—plow soles and disk pans, for example—and once they are removed, every other management decision works better. Trying to find the one tillage or soil density practice that works on every soil is perhaps unrealistic. But we’re working to learn how to farm in the vertical format to achieve and maintain uniform soil density.
Focus on the right thing. No matter how difficult some of our yield information can be to understand, instead of just ignoring it or saying something doesn’t work, it is always worth trying to answer the question of "why."
The test plots have taught us to focus on the right things. If you take one thing out of the equation and don’t take the rest, it can be very frustrating and confusing. Most importantly, remember that on your path to higher yields, there is no silver bullet.