Why Should We Care about EC mapping?

Another Piece of the Puzzle from Central Valley Ag on Vimeo.

by Keith Byerly

by Keith Byerly

There is a saying that everything that is old is new again. But as fast as technology is changing and evolving in agriculture, it doesn’t quite seem like that could be true. But I assure you it is. EC mapping is a blast from the past. 20 years ago, Veris was going to change the way we looked at our fields. But it never quite came true. Sure it developed a nice little niche, but the masses never really embraced it.

So the whole reason I bring this up is, much like WD-40, it has taken time to find a use for EC mapping that makes it useful to the masses. And how we are using this technology to improve your soil sampling recommendations and AquaSystems VRI and probe placement is important. But, I think we need to get on some common ground about what EC mapping does.

EC mapping is a relatively simple idea. I will use a Veris to explain, but the concept is similar with other EC mapping platforms. One pair of coulter-electrodes injects electrical current into the soil, while two other pairs of coulter-electrodes measure the voltage drop. The distance from transmitting coulter to receiving coulter varies, and therefore represents different depths of soil penetration. In overly simple terms, a Veris is a giant Ohm Meter and the coulters are its leads.

And right this minute, I have a few of you ready to check out. Thanks for the science lesson nerd. But hear me out. How it works isn’t the important part, only the framework. What it does is where we start bringing in the science. The usefulness of soil conductivity stems from the fact that sands have a low conductivity, silts have a medium conductivity and clays have a high conductivity. Consequently, conductivity (measured at low frequencies) correlates strongly to soil grain size and texture:

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So, here is where it starts to matter. For us, moisture holding capacity is usually a key component for success. Lighter textures mean we have different fertility, irrigation, and management needs than heavier textures. But, there is where the dual sensors come into play. The depth of our top horizon of soil and how quickly we change materials matters a lot too. Big changes mean challenges when it comes to water infiltration, nitrogen stability, compaction, and more. But what can we do about it.

So this is where we come back to what is new again, and your one thing I want you to remember today. With the advent of better prescriptions for fertility, seeding, irrigation, and hybrid replacement, better base layers of information matter. Much like we wouldn’t build a massive building without understanding the soil under first, we can not build a structure of site specific inputs without a better understanding of what we are building upon. Today, we are using EC mapping to build a better foundation for our Zone Sampling Program and AquaSystems. You had better believe that we are going to use this to build upon for Multi Hybrid planting, VRN and even better grid samples in the future.

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