2 green rows and 6 yellow rows

[GAW46]

We apply ammonium sulphate, MAP and K MAG as a dry starter fert and NH3 shanks on every other row

Fert openers are 2" from seed row, tractor has FWD and duals. We pull the NH3 wagon, straddle  the centre 2 rows

We had early dry weather and then a month of wet followed by dry enough to finish planting corn

Our corn on corn had the 2 rows that tractor straddled, was green and healthy. Even on knolls that used to be subject to some yellow corn. Not this yr. corn was green and healthy from end to end

But: that was only the centre 2 rows. The other 3 rows on each end were yellow from end to end

The wheel marks, fert auger boxes etc. had one green row and one yellow

The planter was checked by agronomist and others for any mis-adjustment

None was found

Each centre box of fert and each NH3 shank gave us one green row and one yellow row, side by side, from same application equipment.

The only thing that was different was that this showed up on corn after corn

Corn after soys or wheat did not have this green-yellow effect

We spread dry fert, soil save in fall and use a field cult to level the field before planting

The soy ground gets field cult in spring only. The wheat ground has straw worked into soil, after harvest and then cult. in spring

All field prearation is done on the angle

Green and yellow rows followed the planter, only on corn after corn

We side dress an additional amount of NH3 after planting and corn is 6-8 inches tall. This is about 40% of total N for entire crop

We have some dry N in starter, some NH3when we plant and rest is side dressed

The corn looks to have a N shortage and will turn green , after the damage is doneâbout 10-12 leaf stage

The problem is that we can not find any part of the equipment that was used on the green rows only. All gave us one green and one yellow from same planter box, NH3 application couture etc

We have 2 rows of green and 6 rows of yellow strips of corn running from end to end of field

Only difference is corn after corn. Soil is sandy and we can not spread fert and plant without dry starter. The soil does not have enough organic or natural fertility. to do that. This looks like we did not apply any side dress fert., which is definitely a yield reducer, in our soil. We grow approx 160 field average over 5 yr. with no irrigation.

Planter drop was perfect, emergence was even and all corn was green untill about the 4-6 leaf stage

Yellow corn has smaller root system, but at 4 leaf stage, roots were the same

Any ideas, no expert in our area has any answers, but this has been seen in other parts of the country. So the extension people and private agronomist have said. Some hybrids are more susceptible and it seems to be in one gentic family, covering different brands. Some hybrids are not so bad, so I do think it may be genetic weakness. Corn is RR but all obvious answers do not seem to apply, such as mis adjusted equipment. Parts are not worn to excessive wear, but that 8 row planter does cover about 1200 acres/yr. The problem showed the same from start to finish. We replace all worn disks etc. every yr.

Fert. auger was new, 3 yrs ago and has worn evenly.   fert went down evenly in the 2 different centre boxes and the 2 end boxesThat means the 2 centre boxes fed 4 rows and one row from each box was either green or yellow. The end boxes had all yellow corn. Compaction test showed no measurable difference, except where the NH3 wagon wheels went, but corn was green on one side and yellow on the other side of wheel mark. Wheels went down centre of row.

We had dry in April, wet 1st weeks of may and finished corn on last part of May

Planting date made no difference

Looks like a nitrogen or starter fert defeciency, but why. We have used this same system and equip. for some yrs. and this is a 1st.

Sorry for long rant, but we have covered all possibilities and think this has cost us big time, when corn decides yield at the 4 leaf and later stage when corn was yellow. We will see if it cost us any rows of corn[on the cob] that might have been

[cropdoc5]

Assuming you have the same variety planted in all 8 rows, because some varieties have a much lighter color green than others, it sounds like you are experiencing nitrogen deficiency from more carbon in the soil or on the surface for the 6 rows versus the 2.  Do you have a chopper head or some other machinery that tends to windrow the residue or leave 2 rows cleaner than the other 6?  If the corn was healthy at the 4 leaf stage the ear is developed then and later at the 8-12 leaf stage the number of rows are determined, so a little stress between the 4 and 8 leaf will not hurt your yield potential. 

I would guess that you will soon see an improvement in the color of the 6 rows as the carbon breaks down and the nitrogen cycle catches up with the needs of the crop.

Cropdoc

[BA Deere]

Since you`re on sandy soil and had dry followed by wet. Is it possible your 2 inside rows had benefits of minor compaction from the tractor tires?  The 6 outside rows remained fluffy and when it got wet the N followed the rain down. What was the planting depth? You said the field came up even but maybe the 2 inside rows were slightly deeper giving the roots a bit of an edge in getting at nutrients. Best of Luck figuring it out.

[GAW46]

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

[Paul]

It sounds almost like the problem we had this year. As it got dry corn started turning yellow. This was corn on beans. Long story short, took a tissue sample and the Calcium,iron boron, copper,zinc and aluminum were way above normal. No explanation why. Corn greened up nice, just could use some rain, curling pretty hard, but some of that could be from damage earlier.