Agronomic Update – June 26, 2020

Fun Fact:  It takes 91 gallons of water to produce one pound of corn….that’s roughly 5,000 gallons per bushel!

Topics for this Update:

  • GDU Accumulation,  current and future weather conditions
  • What’s going on in my fields right now….what’s next….
  • Insect Update
  • Soybean Update
  • Granular Insights Imagery

GDU accumulation & Weather Conditions:

As of June 25th, we have accumulated approximately the following for Growing Degree Days in 2020:

Planting Date     GDD’s 2020         Average GDD     Departure from average

April 21                 945                          930                                      +15 (+.5  day)

April 26                 925                         894                                       0

May 1                     841                         853                                        -12 (-.5 day)

As you can see we have gained some ground versus last update from two weeks ago.  We are currently tracking normal for plant development.

The above maps are showing the 6-10 day and 8-14 day temperature outlooks and the 8-14 day precipitation outlook.  These forecasts are indicating a warmer than normal trend into the first 10 days of July with precip outlook about normal.  This will spur rapid elongation by the plant, and if forecasts turn out as predicted, we will continue to trend normal to slightly above normal for GDU accumulation through this period.

What’s Going On in My Fields Right Now….and What’s Next….

  • Much of the corn crop is in the 9-11 leaf stage right now.
  • At this stage, the tassel is beginning to develop rapidly now and the stalk is continuing rapid elongation.
  • Stalk elongation occurs through the elongation of its internodes.  Next few weeks will see peak susceptibility to green snap….
  • By V10, the time between the appearance of new leaf stages will shorten, generally occurring every two or three days…or approximately a leaf for every 50 GDU’s.
  • In the above forecasts, we will be accumulating 25-28 GDU’s/day, so expect a new leaf potentially every couple of days.
  • At V10, the corn plant begins a rapid, steady increase in nutrient and dry weight accumulation which will continue far into the reproductive stages.
  • Soil nutrients and water are now in greater demand to meet the needs of this increased growth rate.  Keep this in mind as you think about your total N applied so far and what future needs will be….
  • Kernels per row begin around V12 and continue through and up to tassel stage….’just around the corner’….
  • Greatest yield loss from moisture stress occurs from two weeks prior to, to two weeks after tassel.  With current weather conditions and forecasts, the great majority of the crop will most likely be tasseling the week of July 13th.  This will depend upon hybrid and planting date of course.  GDU’s to silk run from 1280 – 1450 depending upon hybrid.  If forecasts turn out to be true, GDU accumulation over the next two weeks will be approximately 360-400 GDU’s….add this to 900 and we will reach 1250-1300 GDU’s by July 9th…..tasseling beginning or ‘just around the corner’ from there.  Bottom line, water needs will be greatest over the next month.
  • The main nodal root system is developing with the last (5th) nodal root developing quickly now.  Brace roots will develop over the next couple of weeks.  See video for root development and moisture…..IMG_0178
  • Waterhemp/Palmer amaranth control in corn is much more erratic this year.   We continue to see re-growth from sprayed plants.  See photos:
  • We are seeing this in fields that have Status or Diflex add to heat up spray tanks.  The heat and wind of the past few weeks has played a role in what we are seeing as many of these plants most likely ‘hardened off’ in the heat and dry conditions at the time of application.

Insect Update:

  • So far seeing very little activity from European Corn Borer
  • Plan on scouting just prior to tasseling for Western Bean Cutworm.  We will have pheromone traps out once again to monitor flight activity.  Check back on our website for updated counts.
  • Still seeing some Thistle Caterpillar in soybeans, but overall pressure is significantly down form 2019.  Keep monitoring for this pest.
  • Should be scouting now for Corn Rootworm larvae.

Soybean Update:

  • Much of the soybean crop is in the beginning R1 (Beg. flower) to full R1 stage.
  • R1 is the timing for any White Mold treatments.  To get effective control on white mold, treatments NEED to go on at R1, with a follow up at R3.  Treatments should be going on now, or over the next week.
  • We are seeing a lot of leaf-cupping in the soybeans.  This is occurring in almost all fields….with or without pre-emerge herbicide applications….with or without dicamba applied.  I still feel like this is mostly environment related….high temps and wind.  So far I have not found any common denominator.
  • Water needs by soybeans begin to rapidly increase at R1 and reach peak at R3 (Beg. Pod).

Granular Insights Imagery…

  • Please contact us if you would like to receive the satellite imagery from Granular Insights.  This is a great tool for scouting purposes.

Thanks for your support!!

 

 

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