Agronomic Update – June 12, 2020….

I think this is a pretty apt description (among others!) for how the year of 2020 has gone.  It’s been a mess in more ways than one.

Topics for this Update:

  • Temperatures and GDU accumulation.
  • What’s going on in my fields right now….
  • Granular Insights & Imagery

Temperatures and GDU accumulation:

As of June 11th, we have accumulated approximately the following for Growing Degree Days in 2020:

Planting Date     GDD’s2016          Average GDD     Departure from average

April 21                 630                          645                                      -15 (- 1 day)

April 26                 577                         610                                       -33  (-2 days)

May 1                     526                        570                                        -44 (-3 days)

Even though we have had heat as of late, we continue to be behind in GDU’s compared to normal.  This shows  how much ground we lost from the very cool May.  The average high temp for May was 8 degrees below normal and the average low was 3.5 degrees below normal.  This goes along way to explaining why, even though our crop was in much earlier than normal, we are still behind and why our stands are somewhat erratic and uneven….however, most stands actually turned our much better than first anticipated at the end of May!

The above photos show the impact of residue on crop emergence and unevenness.  In the left photo, you will see a spot in the field where the plant height drops versus the rest of the field.  This area had more soybean residue and the trash wippers did not do as a good a job moving the residue….as you can see in the other two photos.  Where the residue was moved from the row, the stand is very good and even….where the trash was not moved as well the stand is good, but delayed and more uneven.

These two photos are from the same field (end rows) looking in the same direction.  The first photo was at V1 stage and the second is at V6 (taken June 12th).  The main thing to notice here is the row where the stand is missing and comparing that to the second photo.  Notice how well the row eventually filled in from the second photo.  In the first photo, the seed soil contact was very poor as the soil was very loose and very dry.  The plants in the filled in row are only 1 leaf stage behind.  Just a curious observation!

The above pictures are the 6-10 day temperature, the 8-14 day temperature, and the 8-14 day precipitation forecast maps.  After this upcoming few days of heat, it looks like we will have a cool spell.  This will make it harder to gain any ground versus normal GDU accumulation.  It also means that we could potentially see rapid growth syndrome in the corn as we move through the month of June.  See link below for more info.

https://www.pioneer.com/us/agronomy/rapid_growth_syndrome_corn_cropfocus.html#:~:text=Rapid%20growth%20syndrome%20occurs%20when,acceleration%20in%20plant%20growth%20rate.

What’s Going On in My Fields…..

Overall much of the corn crop looks good.  The majority of the crop is in the 6-7 leaf stage-of-growth depending upon planting date.   From V1-V10, corn gains a leaf collar about every 83 GDUs.  From V10-VT, corn gains a new collar every 50 GDUs, or about every other day.

  • At V6, the growing point and tassel are above the soil surface and the stalk is beginning a period of greatly increased elongation.
  • The growing point is above the ground, so major hail at this point can cause some serious damage
  • You can find a tassel by dissecting the plant
  • The primary ear will usually be located at node 12,13, or 14
  • Determination of potential kernel rows around will be completed around V7 (range of V5-V8)…we are currently at this stage!
  • Kernels per row begin around V12 and continue through and up to tassel stage
  • Nitrogen needs will continue to grow through tasseling and into early reproductive stages.  Nitrogen uptake in corn is now increasing rapidly and will stay that way through tassel (up to 4-8 lbs per day).  Remember that today’s hybrids use nitrogen later in the growing season and into the reproductive phases.  You will want to keep that last shot of N available for after tasseling.
  • We are now heading into the rapid growth and accumulation of dry matter by the plant.  The window for brittle snap will start to grow exponentially over the next few weeks.
  • Watch temperatures as you are spraying post-herbicides on corn or beans over the next several days.  When temps are in the 90’s and humidity is low, the potential for crop response from post-application of herbicides will increase.  It is not recommended to be spraying during the heat of the day if temps are in the mid-upper 90’s…both for potential crop response and herbicide control.

Granular Insights and Imagery

The above photo is a screenshot of a June 10th satellite image from the Granular Insights app.  Corn is on the top half of the photo and soybeans are on the bottom half.  One can readily pick up the soybean plot that is planted in this field from the blue strip to the left of the image.   Granular Insights imagery is now ‘live’ and running with a new image showing up every 1-3 days.  This imagery is an excellent scouting tool as well as diagnostic tool.   Many growers already qualify for this imagery.  Please contact us to get you set up on using this new tool from Pioneer and Granular.

Thanks for your support!  Stay safe and healthy!

 

 

 

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