ReachOut: The Case for a V5 Fungicide Treatment on Your Replanted Corn

ReachOut: The Case for a V5 Fungicide Treatment on Your Replanted Corn from United Farmers Cooperative on Vimeo.

Mike Zwingman

Mike Zwingman

There are few things in the world that make me feel worse than leaving a good putt short.  If you read this series, you know that I like to golf, and you know that I’m not so great at it.  Of all the shots that I screw up though, the short putt is the real killer.  You know the feeling: you’ve got the perfect line and that little ball is rolling right toward that little cup and then…it…just…stops.

Just a little more swing and you might have had a birdie.

This is exactly where we are with our replanted corn.  To replant was a good call—it was, and is, the right line.  Now the challenge is to not fall short: we’ve got to usher our replanted corn to black layer before the first frost.

In a typical year, the threat of an early frost is mostly theoretical.  It could happen, but it would have to come almost apocalyptically early to ruin much.  When conditions force us to replant though, the threat of an early frost becomes much less theoretical and much more real.  The timeline for our replanted corn crop to reach maturity is pushed back into a date range where an early frost is much more likely.

So we’re racing time here, and we’re fighting math.  Our plants need to accumulate 2350 GDUs to reach black layer before the first frost.  On average, we gain 28-32 GDUs per day this time of year.  At 28 GDUs per day, we’ll need all of July, August, and a few good days in September to hit our goal.  That is assuming that every day between now and then is hot enough to bring with it max GDUs—more than likely, we’ll need more than a few good days in September to reach black layer.

That is also assuming that our plants are healthy enough to use every precious GDU that a day has to offer.  Unhealthy or stressed plants make less efficient use of GDUs, so while a day might offer a whopping 30 of them, a stressed plant may only grow as much as if it had received 26.

We have to deal with what the weather gives us (a lesson we’ve learned all too well this year), but we can intervene on behalf of our plants.  Any given day will offer whatever number of GDUs it brings, but by providing for our plants and reducing their stress, we can ensure that they make max use of whatever GDUs they are offered.

This is how we can race time and beat it.

The task at hand is to reduce stress in our plants and leave them wanting for nothing.  We need to provide water, nutrients, and take strides to reduce nighttime respiration, which burns sugars and reduces the efficient use of GDUs.

So water, fertilize properly, and consider the unconventional use of a conventional practice: apply a V5 fungicide treatment.

That might sound a little crazy—to use a fungicide on replanted corn—but when it’s 75 degrees and 80% humidity at 7 a.m., nighttime respiration is a reality as is its negative impact on your plants’ growth.  In conditions such as those we’ve been experiencing, corn plants work to survive—growing is a distant second on their list.  A V5 fungicide treatment eases their task and allows them to put their full energy into growing again—21st century practices to the rescue!—which speeds their journey toward maturity, which is good for us as we watch the calendar wind toward fall and frost.Header1

In one of the most challenging growing seasons in recent memory, we’ve yet managed to work ourselves into a good position.  After spending a bit of time in the rough, we’re finally on the green and lined up for the putt.  Let’s not leave it short.

For those of you who didn’t have to replant, check out James’ article Wednesday morning for the story on stress mitigation during the reproductive stages of your corn.