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August 8, 2018

Trip Report - Iowa and Northern Illinois

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

On Saturday, August 4th, we took a swing through Iowa and northern Illinois. The comments below reflected my thinking on Saturday, which was before the repeated showers swept across central Iowa on Sunday and Monday. The rainfall over the last two days seemed to have missed much of central and southern Iowa, but they helped the north-central part of the state. The comments below reflect my opinion before the recent rains and I decided to not rewrite them in order to reflect the reality as of last Saturday.

I will be honest, I am not sure what to make of the crops in Iowa. In northeast Iowa the crops are excellent, maybe some of the best I have ever seen, while in southeast Iowa the crops are suffering from moisture stress and in northwest Iowa they suffered from too much water.

In the latest weekly crop report, the soil moisture in northeast Iowa is 7% short to very short, while in south-central Iowa the soil moisture is 93% short to very short.

Northeast Iowa - The corn in northeast Iowa is generally excellent. The crop is tall, uniform, dark green, very healthy, high plant population (it looks like every kernel germinated), high ear count, large ears, and a very high yield potential. The corn in northeastern Iowa will only need one or more good rains and the crop will essentially be made

The soybeans in northeast Iowa are also in very good shape. They are tall, uniform, really dark green in color, healthy, heavily podded with a very high yield potential. The soybeans still need a couple more good rains before the crop is safe. The lawns in northeast Iowa are dark green and growing.

Central, Southern, and Southeastern Iowa - The situation in this part of Iowa is very different. The crops here are suffering from oblivious moisture stress and they are in badly need of a soaking rain. The corn in this part of Iowa had a high yield potential at one time, but that has slipped away. The corn is pale green in color, the bottom leaves are firing, the ear count is high, but the ear size is small and the yields are declining. The moisture stress is especially evident on the lighter soils. The lawns in this part of the state are brown.

The soybeans are also exhibiting moisture stress especially on the lighter soils. On the heavier soils, the soybeans are still doing fine, but on the lighter soils, there are light green in color, wilting in the heat of the day, and losing yield potential.

Northwest Iowa - The crops in this part of the state were impacted by too much rainfall earlier in the summer. There are a lot of empty holes in the fields where the crops were drowned out. The corn on the higher ground looks fine. It is tall, dark green, higher plant population, and it has a high yield capacity. On the lower ground the corn is pale green, stunted, lacking nitrogen, and it has a much lower yield capacity.

The region is exhibiting the typical pattern of when there is ponding. There may be a spot where all the plants have died surrounded by a ring of corn that was not killed but suffered significant damage. Then when you get away from the drowned out spot, the corn is normal.

The soybeans in northwestern Iowa seemed to have suffered more than the corn from the excessive moisture. There are a lot of holes in the soybean fields where the standing water killed the soybeans. There are also areas where the soybeans are short, stunted, yellowish green in color, and very low yielding. I don't want to be too negative though. Outside of the wet areas, the crops looked fine. Needless to say, the lawns are green in this part of the state.

Southwest Iowa - I cannot personally comment on southwestern Iowa because we did not travel to that part of the state on this trip.

Iowa Summary - Collectively, I thought the crops in the state were not as good as I expected. Yes, part of the state had probably some of the best corn I have ever seen, but there were other parts of the state that looked pretty tough. There are six other states that have a corn crop rated better than Iowa - Nebraska, Wisconsin, Illinois, North Dakota, Minnesota, and Ohio.

I think for corn, future rains will maintain the crop where it is, but not bring back what might have been lost. The soybeans are a different story. A couple more good rains for the soybeans and the crop could keep adding to its yield potential.

In the August Crop Report, the USDA will need to account for the holes in both the corn and soybeans fields in northwest Iowa and in southern Minnesota by reducing the harvested acreage.

Northern Illinois - In the northern part of the state, the crops looked very good, but you could see that the weather has been dry and that some moisture stress was starting to develop. Both the corn and the soybeans looked very good with very good yield potentials. If the weather during August ends up dry, then you might trim the corn a little, but it would probably be more of an issue for the soybeans.

The driest part of the state is the west-central part along the border with southeastern Iowa and northeastern Missouri.