ReachOut: Maximizing Yield Potential

ReachOut: Maximizing Yield Potential from United Farmers Cooperative on Vimeo.

Mike Zwingman

Mike Zwingman

I drive 53 miles to work each day.  It takes me 43 minutes.

Which means that I have to average 74 MPH to cover this distance in this time.

Of course, 74 MPH is an average.  I don’t drive 74 down O Street in Lincoln.  I match my speed to the road: 45 down O, 65 on Highway 34, 75 (plus a little, because I can) on I-80.

If this makes sense to you, then you, my friend, might be a perfect fit for variable rate seeding and fertilizing.


Variable rate seeding and fertilizing utilize yield potential maps to determine which fields are capable of yielding at high levels and which are not and adjust seeding and nitrogen application accordingly.  The two practices are most effective as a package.  Perhaps you’ve had the experience of increasing your seeding rate with little to no effect—it’s a pretty conventional practice to play around with plant population, but inattention to the additional nitrogen that the increased population requires usually renders our experiments with plant population ineffective.

If you’re unfamiliar with yield potential maps, which are based on midseason biomass measures, they look an awful lot like the actual yield maps that you have in your combine, but whereas actual yield maps report actual yield in numbers, yield potential maps report yield potential in percentages.  If you’re thinking, hey, that sounds like they’re pretty similar, they kind of are, but with one very important difference: the percentages reported on yield potential maps are historical.  The biomass measures that the maps are based on are taken from satellite imagery that goes back as long as said satellites have been orbiting earth.  Since we put a monkey in space, we have biomass images of your fields.  Maybe you want to put your tinfoil hat on now, but that historical record is an astoundingly useful piece of intel on your yield potential.

Both maps though provide proof that your fields are different from each other, especially in terms of productivity.  If we know about these differences, why should we continue to treat each field the same?  The answer is that we shouldn’t and variable rate seeding and nitrogen application allow us to do so.

Those fields that show up on the yield potential maps in a nice bright green are your horses.  They’re yielding at a rate above average for your total farm and it’s possible that you haven’t even maxed out their potential.  Variable rate seeding and nitrogen will increase seeding and application rates in these fields to capitalize on this potential.  Those fields that show up in red?  Those are the ones that struggle to produce for whatever reason and consistently yield lower than average.  Variable rate seeding and fertilizing won’t forget about these fields, but it also won’t shuffle resources their way that would better pay off in other places.

Header1Essentially, variable rate seeding and nitrogen application match your speed to the road.  This both maximizes your potential—underplanting a field that could handle more is like going 55 MPH on I-80—and saves you money—overfertilizing a field that just won’t produce is like going 60 down O: there’s a financial penalty.  That waste of nitrogen is your speeding ticket.

My last speeding ticket?  May of 2011.  The money I spent paying it?  Man, I would have rather bought that smoker…