Posts: 19
Registered: ‎06-13-2010

Re: 2 green rows and 6 yellow rows

The residue idea might be worth having a look


The problem showed up on corn after corn, only,.


Have used all equipment for past 3 yrs. and this the 1st. Usually we have yellow spots in the field. This time we had 2 green rows in those yellow spots


Have to take my word that everthing is exactly the same on all 8 rows. Had independant measurements in the dirt  and every other possible measurement, including field, done by others


One NH3 shank was off centre by 1 "  2 centre fert. starter rows were 2 1/2" and all others were 2" All parts are worn equally and started out new. Corn root mass was more than 21/2" big before 4 learfstage, by a bunch


I am wondering:


We may be creating a zone of higher corn resudue in those centre 2 rows


I find it hard to believe that we can plant the same ground over and over again and not wander a little bit, but maybe 30" is enough


The combine is an IH rotary with straw spreaders and spreaders are drop down [longer shaft] suposed to get the sieve material


However, some material must be coming directly off the sieves and missing the spreaders [not sure, have to watch in wheat harvest]

Header and planter are both 8 row


We do fall and spring tillage, so the residue has some time to start decomposition


All corn is BT and RR stacked


Combine tires are 30.5 and header is offset a little, so we use a stalk smasher on one side to protect the tire that has to run on top of that row of corn stalks. Header frame was extended to 9 row ^24` and brought back to 8 row, 30` from original 8 row wide.

That corn header has seen a lot of changes, over the yrs. but same stuff either goes down through the header or through the combine, and deposits sieve material  in the general area of the green corn, depending on how straight we plant, yr. after yr.


Sandy soil, 40# of actual N going on as starter, another 40-50 at planting with NH3 wagon pulled behind planter

We also use MAP and some K-Mag with the starter. Total product is 200#/acre, dry starter, so a lot is ammonium and MAP

Starter is applied in a 2x2 band, things might move around, but those 2 green rows sure stayed from end to end of field, no matter if things moved or not. It was not hit or miss.

Is it possible to run out of N [40# actual] before we get past the 4 leaf stage. One guy doesn't use any and is beside our farm. He did have cattle manure some yrs. ago. but not for last 10 yrs. He uses no N in starter and has good looking corn. Corn all looked good when it was sprayed 1st time

Only compaction we could find was in the 2 rows that the NH3 wagon wheels ran on, but on side of wheel track was green and the other was yellow. Wagon wheels ran down centre of row, straddling the 2 green rows, and most we could find was 1-2 inch variation, between wagons


Sure does look like N defeciency, but can we have that much build up of residue, given our drop down spreaders and how straight can a person plant, yr. after yr. Why did thise 2 rows get more N and how much do we need for the other 6 rows, assuming residue was decomposed enough to give back some N and not steal it from the corn We side dress remaining 1/2 of total N when corn is about 5 or 6 leaf stage. Corn was yellow before we started to side dress.[ 160-190 actual N/acre depending on yield potential.]   5 yr yield average is about 160/acre,dry,or little better, last couple of yrs. . We have 40' tool bar and can do about 150-200 acres/day This yr. corn was taller when we got done, because it grew so fast. Corn is turning green, but yellow corn now has a smaller root mass.


Why do we need so much N so early, at 4 leaf stage??? We got about 40 and 40 actual with starter and NH3 at planting time.  Is  higher corn residue in centre 2 rows even possible or a good explanation??? We do have sandy soil and low organic material, but we saw it on low ground with higher organic material. Corn after corn and centre 2 rows was biggest constant possible variation, so far.

We are not the only folks with this problem, but others have random yellow rows, Usually we would have weaker spots in the field. We solved the yellow corn in weaker spots for 2 rows and got a lot of yellow rows as a result.


Long story but trying to cover all the possibilities isn't easy. I still looking at the N but need to wait on leaf analysis and an explanation, that we can do different. Was told not to take cutting torch to the corn planter. and sell for junk price. J.D 7000