May 23, 2019   
  Issue 3

Corn yields, delayed planting.  

This info is from a date of planting study from the ISU Northern Research Farm near Kanawha in 2017.   Info from 2014 -16 is available here .  
                        P0157AM                   P0589AM                   P1197AM       average
                        Yield   H20                 Yield   H20                 Yield   H20
                        bu/a     %                    bu/a     %                    bu/a     %
5/9/17              245      16.7                 274      16.7                 303      19.4         274
5/30/17            229      18.0                 241      17.4                 253      24.2         241
change            -7%      +1.3                -12%    +0.7               -17%     +4.8        -12%

  -  The delay in planting from early May to late May shows a yield decrease of 1.5 bu/acre/day and an increase in grain moisture of 0.1 point/day. 
-  The same study at the ISU NWRF/Sutherland had less impact from delayed planting.
-   Planting dates in mid-June produced ~120 bu/a yields with 20 to 30% grain moisture.
-   Corn hybrids require 7 fewer GDDs per day of delay to mature with delayed planting.  
-   The cost of drying 200 bushel per acre corn is about $7.00 per acre per point.  
-   Consider June 5 as a date to change from a corn crop to a soybean crop - because of reduced corn yield and added corn grain drying costs.
Soybean Planting
This date of planting information is from the ISU Research Farms near Sutherland (NWRF) and Nashua (NERF).   The info from the NWRF and the NERF might be optimistic - the info from PM1851 is based on more data and is more conservative.
Planting date               2014-16 NWRF          2014-2016 NERF              ISU PM1851
                                    -------------------- bu/a ----------------------              ---% yield ----
late April                                                                                                         100
early May                            69                                   59                                  96
mid May                              65                                   60                                  99
early June                            60                                   55                                  81
late June                                                                                                           61
early July                             51                                   46                                 33

·   Actual soybean yields may to be 45 to 55 bu/a when planted ~June 10.
·   Use an early group II variety until June 15 -20. 
Prepared by:
  Paul Kassel- Extension Field Agronomist


Phone:  (712) 262-2264


Serving Clay, Buena Vista, Dickinson, Emmet, Hancock, Kossuth, Palo Alto, Pocahontas, Sac and Winnebago Counties



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Prepared by Paul Kassel, Extension Field Agronomist

Phone: (712) 262-2264, Email: