AGRONOMIC/BEG. HARVEST UPDATE – September 20, 2023….

 

   

Topics:

  • GDU/Weather Update
  • Corn – Soybean condition & Early Harvest trends…

GDU/Weather Update:

As of September 20th, we have accumulated approximately the following for Growing Degree Units in 2023:

Planting Date     GDD’s2023          Average GDD     Departure from average

April 17                   2985                            2888                              +97 (+6 days)

April 26                  2940                            2829                              +111 (+6 days)

May 9                     2810                             2720                               +90 (+5 days)

June 1                     2447                            2435                                +12 (even)

We have continued to gain ground on GDU’s since the last update on Sep 6 by a day or so.  All early planting dates have reached even GDU’s to finish the crop.  June dates still need some time.

The 6-10 and 8-14 day temperature and precipitation forecast maps are all showing above normal temperatures and precipitation.  Above normal temps are much needed for drydown but the precipitation forecasts may slow harvest down for much of what’s left for September.

Corn – Soybean Conditions…

  • Most of the April/May planting dates have reached black layer, or are very close to doing so.  The June planting dates on corn still need 10 days yet…
  • So far corn staygreen is holding up in most fields, but the corn crop is starting lose its ‘luster’ now, especially after the last few warm days (which were much needed for finishing the crop and moving soybeans along).  Continue to monitor staygreen over next few weeks.  Monitor those fields that lose color the quickest over next few weeks as they will be the first ones to go after for harvest. 
  • Grain moisture drydown is dependent upon temperature and ear husk structure.  On average, it takes 15-20 GDU’s to lower grain moisture each point from 30% down to 25%, 20-25 GDU’s per point of moisture from 25% to 22% and 25-30 GDU’s per point from 22% to 20%.  A high of 75 degrees and a low of 55 degrees equate to 15 GDU’s, which should roughly take a point of moisture out per day when grain moisture’s are 25%+.  So temps in the mid-70’s for highs and mid-50’s for lows should take corn from 30% to 25% in a week’s time.
  • Early harvest moistures on dryland and early-maturity hybrids planted in April, are running mainly 22-28%.  This will vary of course by area and hybrid, but we can tell that the early maturity hybrids are starting to dry down somewhat, even in the irrigated….
  • Silage yields have been trending above normal overall…hearing a lot of low-30’s to high-30’sT/A for tonnage.  A local silage plot had a top yield of 40.4T/A from a new Pioneer hybrid, P17677Q.  Just a comment, usually good silage yields mean a good grain yield….not always, but starting out with high silage yields can’t hurt…
  • First few corn yields coming out of dryland are better than expected….over 150-180+ bushels from early yields.  P1413AM performing well early….
  • Same for dryland soybean yields….better than expected early trends….50’s-mid-60’s/A on average….depending upon rainfall, etc.
  • Not enough yields from irrigated, for both corn and soybeans, to get a trendline yet…mainly early-group II maturities coming out now on soybeans.
  • Soybean harvest moisture: There is an average yield reduction of 7-8% when going from 13% moisture to 8% moisture soybeans.  This means an average loss of 6 bushels/acre (using an 80 bu yield) just in moisture, along with potential reduction from header loss, etc.   The below chart shows the average yield lost from lower harvest moisture and delayed harvest over five year on-farm study from Pioneer.

All for now.  As harvest progresses, we will text out plot info and updates.  Have a safe and successful harvest!!

Starman Seed Service, Inc.

 

 

 

 

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