Posts: 19
Registered: ‎06-13-2010

2 green rows and 6 yellow rows

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