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  • Writer's pictureWendell Koehn

March 1, 2019 Corn/Soy Update

To cut right to the point: we are facing a narrow work window this spring as we look at preparing to plant and the planting operation itself. David Hughes, field agronomist for Beck’s Hybrids sent some thoughts that I want to share with you. Dwight Eisenhower famously said: "planning is everything, the plan is nothing."  Keeping top priorities in our minds will be important when the planning is derailed by adverse weather. We may need to scrap that bullet proof plan that looked so good early on when at the kitchen table and pivot quickly in the field to handle the curve ball that the weather or some other outside influence throws our way. David’s input will help utilize the working hours:

When we have more to do than what we perceive as time to get it done in, it can get stressful.  These times require thoughtful planning and prioritization. Develop and then trust your prioritization and planning process.  Allow yourself the flexibility to hire out operations that have to be conducted in a timely manner if you are unable to do them yourself. 

Understand which things are priorities and which are not even if it means adjusting your own conventional thinking.  

            **For example, nitrogen (N ) application for corn is not an operational priority ahead of planting or weed control (see priority list below)**

Also think outside of the box if you have to. 

            **  For example, If it is time to burndown winter annual weeds and soil conditions do not allow ground-sprayer application, consider calling in the birds (aerial applicators) to apply burndown**

The following is how I would prioritize pre-plant operations at this time (if not already completed):

  1. P, K, S, and Zn application where soil tests have shown these nutrients to be in the low to very low category. a.       If lime piles aren’t already on the ground, I tend to refrain from heavy lime application until after harvest once we hit this time of the year.  This is especially true in no-till fields. The soil compaction that can occur from lime truck running on ground at high moisture content is significant.  Additionally, non-incorporated, high rates of lime on the soil surface with little to no time to breakdown can increase seedling injury with some of our residual chemistries.   It is better to wait until harvest and be ready to roll with the lime trucks then when the ground is dry.

  2.       Planter maintenance, repair,  updating, and planter and meter evaluation to know how to optimize settings for your seed sizes. Seed size has little to no impact on achieving genetic yield.    Accurate product placement is more important to yield than seed size. 

Seed size can impact singulation if planter components are not set correctly.  Learn your planter manufacturer’s settings and recommendations for various seed sizes.  

Seed size can impact germination/emergence in some situations.  Very large seed tends to struggle a little more in drier soil because they require more water to swell and germinate.  Very small seed tends to struggle in cold, wet soils because they have lower energy reserves in the seed itself. 

                                                              i.   Recommendation with extremely large seed:  Make sure planting depth reaches the uniform soil moisture zone even if it is a little more than 2 inches deep. 

                                                            ii.   Recommendation with extremely small seed:  Consider use of Amplify-D (a PFR Proven product) as it adds chemistry, AMP (adenosine monophosphate), to the seed that can assist with meeting seedling energy requirements and help jump-start the seedling’s own production of ATP (adenosine triphosphate).

                                                           iii.   If equipped, apply phosphorus (P) starter

3.       Review product placement plans with Wendell and anyone who will be planting corn on your operation to make sure everyone is on same page for what products should go on what fields.

4.       Evaluate fields for weed pressure and apply burndown as soon as conditions are right.    We did not get a high percentage of fall application done,  so this is critical. Starting clean is critical for elevating soil temperature sooner, allowing wet soil to evaporate and dry out some,  improving the efficacy of pre-emerge residual herbicides, and removing egg laying sites for black cutworm moths and flea beetles. . Early burndown application is also critical to achieving less expensive, resistant-marestail control. 

5.       If tillage operations are needed, perform only when conditions are right.  Do not perform tillage when soils are too wet as soil compaction and degradation of soil structure will occur.  These mistakes can cost you much needed water later as water infiltration rates become significantly reduced on soils with compaction and poor soil structure.

6.       When conditions are right, PLANT.   This is even if you have not been able to apply N yet.   Average field soil temperature should be 50F or greater and soil moisture conditions should be that you cannot make a ball or ribbon that stays together when thrown up against your other hand or the ground.

7.       Apply N to meet corn needs. I have intentionally placed this as the least of your worries.  Absolutely, if the weather allows you to get some of your N on ahead of corn planting do so.  That is fantastic. But do not stress if you are unable to apply N before planting. Also, do not fear other sources of N if it does not work to apply anhydrous (NH3)-ammonia.   You will simply need to understand the best management practices associated with uses of other N sources. In fact, in some cases anhydrous application may do more harm to our soil condition than good if we push application when it is too wet. 

a.       Beck’s PFR research has shown in comparing various pre-plant, at planting, and side-dress N applications, that optimum yield can be obtained with some N on at planting and the balance of the N applied by the V3 growth stage. 

b.      Many site-years of university research in Missouri demonstrates that there is zero yield penalty when 0 N has been applied by planting as long as it can be put on as late as the V7-V10 growth stage.  This goes against some of our conventional thinking (mine included) that we impact kernel rounds with insufficient N by V6. However, in personal discussion with Dr. Peter Scharf, State Soil Fertility Specialist and one of the best N researchers in the country, he showed me where they had actually taken ear “round” counts under different N treatments and there is no significant difference among “0” preplant-N and pre-plant N on kernel count where the balance of the N was not applied until approximately V7 growth stage.  The following is an excellent graph showing research from almost 10 years of University of Missouri work on Corn N timing impact on yield. Dr. Scharf also included data from other states to show that there is general agreement in the data. 

c.        After review of Peter’s data and consideration of my personal observations and experiences, I am comfortable if N cannot be applied until the V7  growth stage. So we have time! Like I said, if you can get some on before that is great but is probably one of your lower priorities. There are two unique cases where I recommend prioritizing some pre-plant N application. 

                                                            i.   Corn following a rye cover crop

                                                            ii.   On fields being planted to early maturing hybrids where our expectation is for these hybrids to achieve yield potential with fewer growing degree days to play with.

End of David’s thoughts

If you need anything or have questions for your particular situation call me anytime. We can work out a priority plan. 


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