8/9 Corn Update

Corn Update:


Rootworms are still the current hot topic.  Marcus has some rootworm traps out in fields again this year because when we dug roots a few weeks ago we noticed more feeding than normal.  Of the 21 fields with traps out (we have more we haven’t collected yet), most of them were higher than what we saw at any point last year.  Quite a few of them had numbers above 20 which means it is something to start to manage for in the future.  Conditions were ideal for their survival this year due to drier conditions (non-saturating rains) in June.  Higher survival rates mean more eggs being laid for next year (this is the same reason we have high pressure– from the dry weather last year).  They are currently still in the corn, but if you have a lot of pollen in soybean fields, they will start to migrate that direction as the cornfields are mostly done shedding.  Waterhemp, giant ragweed, and volunteer corn appear to be the main sources of pollen in our soybean fields.  This will increase pressure on the rotated acres for next year.


Trap Years Corn beetle bomb in past # beetles
Week #1
1 20+ No 8
2 20+ No 7
3 30+ No 82
4 24 Some 2
5 5+ Yes 2
6 5+ no 14
7 15+ Yes 15
8 15+ no 48
9 2 no 7
10 15+ no 47
11 10+ no 14
12 5+ yes 8
13 5+ no 6
14 10+ no 96
15 10+ no 109
16 10+ yes 0
17 5+ yes 2
18 5+ yes 0
19 5 yes 0
20 10+ no 20
21 10+ yes 17


Many of the corn plants are currently at / near R4. At this point we really just need sunny, cooler, days.  The heat will push the maturity along quickly.  The longer we can make the grain fill last, the deeper the kernels will be.  Remember the chart we sent out last week showing how many thousands of kernels per bushel?  The longer we make the plant take the fill, the deeper those kernels (to a point).  We still need sunshine for photosynthesis and water for nutrient uptake, but bright sunny days with highs in the 70’s instead of the 80’s would be beneficial and lows in the 50’s would be great.  That isn’t too much to ask now, right?


Deep Sink: We have some good potential in the corn, however, we also have a strong pull to fill all these kernels.  The rain will help move the nutrients to the roots which will help, but any dry areas will cause the plant to cannibalize the stalk to fill the ear.  The plant has one job – produce seed.  It will do this at any cost, including pulling from the stalk.  Speaking of pulling nutrients out, all those plants we’ve heard about with 2 ears, go check those.  I haven’t found any that will produce any actual kernels yet.  Most of them look like they pollinated but there are no seeds on them, they are just rotting away.


Reminder: National Corn Growers Contest entries are due August 15th!  If you have not done this before and think you have a prime spot for a weigh check, let us know, we can help you get signed up.  Signing up with a Pioneer hybrid in your field gets your entry fee and membership paid for by Pioneer as well!  If you win regional and national prizes you get cash as well!