AGRONOMIC UPDATE – AUGUST 17, 2021….HOW DRY WE ARE….

 

Just a Quick Agronomic Update…..

Topics:

– Growing Degree Unit Update

– Quick Crop Update/Water Use/Weather

– Corn/Soybean Insect Update

GROWING DEGREE UNIT UPDATE
As of August 16th, we have accumulated approximately the following for Growing Degree Days in 2021:

Planting Date     GDU’s2021          Average GDU     Departure from average

April 24               2214                        2015                        +199 (+9 days)

April 30               2160                        1955                       +205 (+9 days)

May 6                   2081                       1920                       +161 (+4.5 days)

We have gained about 2 days since the last update on August 6th.  The crops show this as well, as much of the corn crop is Dough to Full Dent depending upon hybrid maturity and planting date. and soybeans are late-R5 (Beg. Seed) to mid-R6 (full seed) stage.    Compared to last year, we are basically the same for GDU’s and growth stage….soybeans seem a little ahead of last year though. We like the kernel counts that we are currently seeing in the fields, however, the final kernel depth and test weights will determine overall yield.  The wind event from July 9th, however, will have an effect on final yield as the more severely leaning plants have reduced ear size and spottier pollination, along with potential for weaker stalks.

WEATHER UPDATE
  • Relative Humidity – Since last update RH has been 10% below normal, or 65% vs. a normal of 75%.   This has influenced a couple of things….reduced potential disease outbreaks but has increased crop ET rates and the potential for increased numbers of spider mites.
  • ET rates – ET rates over the past 10 days have averaged .23″/day, or 2.3″ total for this period.   This is equivalent to four circles in ten days @ .60″/circle.    It has been difficult to increase soil moisture profiles in this time frame.   It has been especially hard to shut down much at all in the sandier soils.   This has been driven higher by the lower RH and breezy, south winds.  If current temps and conditions continue, expect much of the same over the next 10 days.  See tables below for Water Use for soybeans and corn.
  • Precipitation – Yeah, I know….what is that?  We should normally receive 4″ or rainfall in August.   You can see by the map what we have actually received, which is next to zero for the month.
  • Hopefully it will rain on Friday/Saturday.   Hope springs eternal….and remember, we are always one day closer to a rain than the day before…..
  • Sunlight – Since the last update, we sunlight has been 9% above average over the past ten days.   This should be a positive to yield and plant health.   For more info on the affects of the smoky haze, please see the following link from Pioneer…..https://corteva.showpad.com/share/OUqawYGy93kP4v4p9IhpB
CORN/SOYBEAN INSECT UPDATE
  • Spider Mites – Just starting to see an increase in spider mite colonies in some area fields.   The weather conditions as of late are conducive for an increase in infestations of this insect.  We still have a month of grain fill left, so keep an eye out for this pest to keep it from ‘turning’ your corn field too ‘fast’.
  • European Corn Borer – Currently seeing low infestation levels of this insect, however, numbers have increased this week vs. last week.  If you have popcorn or conventional corn acres, keep this pest in mind also.   Treatment for this pest should go on this week for best results, which means any treatment is as much a preventative treatment as a ‘must do’ treatment.
  • Soybean pests – so far, insect activity in soybeans continues to be very light.  This is the lightest current leaf defoliation that we have seen for some years.  We have not seen much for soybean aphids or bean leaf beetles so far.  Expectations for major outbreaks of these pests are low.
In the FYI category:

The following link https://www.agry.purdue.edu/ext/corn/news/timeless/YieldTrends.html is an interesting article on Historical Corn Grain Yields in the US.  Highlights of the article:

  • Corn grain yields in the U.S. have steadily increased since the late 1930’s.
  • Only two major shifts in U.S. corn yield trends have occurred since statistics were first published in 1866.
  • Year-to-year departures from trend yield are influenced primarily by year-to-year variability in growing conditions.  (so true…italics mine)

Below are two tables from the article….

 

Reminder that the Pioneer Customer Appreciation Supper is this Friday evening, August 20th.  Celebrating 25 years of business!   Bring the family!

Thanks for your time!

Starman Seed Service, Inc.

 

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