Build a Bigger Sink

Build A Bigger Sink from Central Valley Ag on Vimeo.

by Mike Zwingman

by Mike Zwingman

We’ve gotten some blowback on some new technology lately. For some of you at least, new-fangled tech didn’t produce the numbers we were expecting. The Twittersphere is alive with some colorful recriminations of things like Y-drops, which are, in summary, being called a waste of time and money.

Which isn’t true.

But don’t split just yet.

Numbers are what happened. Like the score of a basketball game, they show you the outcome, but not what really went on. Not how we got there.

To determine that—how we got to a place where technology like y-drops netted us no more yield—the four Rs are perfectly instructive. They provide a guide for our nitrogen-related decisions and can help us understand the dynamic situations into which we’ll very soon start planting seed for a new season.

If you’re a regular reader here, you’ll remember that the four Rs (rate, source, placement, and timing) are interconnected, meaning that each decision you make regarding one affects the other three. There’s no perfect place to begin our investigation, but I do think there are salient notes on three of the four that might point us to an explanation of the current problem:

Placement: Like I said, y-drops are not having a very good day on Twitter. But they should work—both theoretically and according to facts and trials. Over and over, in study after study, investigation after investigation, in trial after trial, precision of placement has proven advantageous.

Timing: Just as precision of placement has repeatedly proven to be worth it, so has precision of timing. We know that time is the great enemy of nitrogen for our purposes. Too much time between the application of N and when your plants actually use it spells lots of loss (soil will do what soil will do). One solution to this has been a split application of N, which pushes the application closer to the time of need, and which should make for less loss and more yield.

Source: Source kind of is what it is, so long as you’re not being a total doofus about it, like trying to topdress with anhydrous. It matters yet because it is necessary, but is less of a factor in this investigation again so long as you’re minimally informed.

Rate: Which leads us to rate…

Let’s summarize first:

You used a technology that provided precise placement, something proven to drive yield numbers higher.

You were precise in your timing of application, also something proven to drive yield numbers higher.

You used an appropriate source.

Yet all of the sudden, the numbers don’t add up.

Perhaps because—drumroll please—your rate was wrong.

This, I suspect, is the crux of the problem. We are very accurately overapplying N.

We very well may be overapplying N just enough as to mask the yield increases promised by technologies like y-drops. The problem is not that these technologies don’t deliver—it’s that we’re mismanaging an R—our rate— by a percentage large enough that they can’t do their work. The four Rs are nothing if not dynamic—if you ignore one, you can never have four R soil fertility program.

To some of you the thought that we are overapplying or mismanaging N is a pretty strong statement, but it was meant to be somewhat exaggerated. The reason why we may be overapplying or mismanaging isn’t completely on us, I am going to put some of the blame on the soil. In doing that we need to realize that Placement and Timing are the two best tools we have in mitigating the influence the soil has on Rate being right or not.

To apply N at the right rate, the sum of our source (our application rate plus mineralization) needs to equal the sum of our sink (a number that takes into account things like yield goal, hybrid selection, plant population, NESP, stresses around ear development, weather during grain fill, etc.) We may never get this equation perfect, but we can get it close. And the “failure” of promising technologies last season makes me suspect that we need to do some more work to get it closer. We are going to focus more on the Sink-Source relationship as the growing season progresses.

With all that is at long term risk, I say we give technology another chance and when we do account better for the efficiencies we are trying to create by lowering our Rate when using them. Let’s not toss a technology because we tried it wrong the first time though. To heed this red flag and reevaluate our rate leads us to the opposite, and honestly, friends, into the future as well.