9/13 Corn Update

Corn Update:


Silage season is in full swing, and in some cases winding down depending on maturity and where the rains were located.  Earlage and high moisture corn will be next.  Keep us up to date with any questions / comments / concerns you are seeing as you get into the fields.


Frost issues – We’ve had this question from a few people so I wanted to share this from the plot night.  Below are 5 plants ranging from frozen down to the ground, to very little damage.  You can see how these plants progressed and what the ears on these plants looks like.  As you can see, only one of the really damaged plants had a runt or smaller than normal ear.  The others were able to recover.


Why do we always reference 2500 GDU’s?  2500 is the magic number.  2500 is where our “normal” maturing hybrids reach physiological maturity (black layer).  This year is a bit different, though.  Walking through the plots today, it appears many of the hybrids have almost slowed down.  I would expect that after we had 85 GDU’s last week.  However, this week looks great with warm weather and very little rain in the forecast.  The forecast for the next 7 days is to get us close to 2600 by next Monday. I’m not sure if all the hybrids at 103 day CRM and below will be there or not, but they should be close.


That leaves us about 100 short to get through the 106 day hybrids. The calendar says it will take another week to get there.  Considering that is only 2 weeks and some of them are still 3/4 milk line, that still lets them fall in line with what we expect.  Just like the past year – we will get to use the last week of September for dry down and anything in October is just a bonus.  Remember 2019’s dry down chart?  We had a couple of weeks where we had 5 and ZERO GDU’s in two consecutive weeks!   Hard to dry corn in October with no temps above 55 degrees.  Let’s hope its warmer than that in 2021.


We still start out dry down study soon.  This isn’t a perfect system and there are going to be differences.  But what we look for here are trends.  What is holding moisture and what drops a lot in a week.  Here is a copy of last year’s dry down to give you an idea of how wet stuff was – hopefully, we can start next week and have some good numbers like last year:


Weigh Wagon vs Yield Monitor:


One other thing we see a lot as we get into harvest – differences between the monitor and the weigh wagon.  This always happens each year, and doing split planter comparisons or plots, it can only be worse.  The kernel size, test weight, and kernel shape can change the way the impact plate on your combine reads the yield.  Here is the difference we saw in our own plot last year comparing the monitor to the weigh wagon.  We have years of data like this and the ranges vary greatly each year from higher than expected to lower than expected.  Most of the time the differences go both ways.  Using an example from below – if we had P0595 and P0688 split planted, the yield monitor would tell me P0595 is 50 bushels better than P0688, but in reality, the P0688 would be 8 bushels better (NOT 50 bushels less)!