Early Crop Evaluations

by | Jul 12, 2020 | Crop Watch

And a belated Happy July 4th to everyone. In most years many towns around the Midwest have their own small town parades and celebrations. Many floats, marching bands, patriotic floats, town queens, cake walks, bingo games, etc. are all things that many of us grew up with that remain etched in our memories from a long time ago. I remember the big parade in Meyer, IA, population now of 14 people, with my grandfather, Arnold Koenigs, in charge of the parade, proudly driving his team of Percheron horses and being all excited about the different floats. He was young then, and passed in 1976 at age 75. Times and method of living changed in March of this year and except for the fireworks, none of those festivities were held. There were still family get-togethers and BBQs but many people were still quite reserved. Most people are ready for life and things to get back to normal.

I hope you did one special thing over the 4th with your significant one and family that they can smile about. We saw our three daughters down in St Louis last weekend as two of them rendezvous on the first leg of a trip to Florida where Evan is from. We saw fireworks at a family gathering south of Ames and went up to Pine Lake Park near Eldora.

Early Corn Crop Evaluation

The last three months have been a whorl wind of activity. Much of the field prep and trips thru the fields have been completed, for corn and bean production, with only trips with high clearance equipment or airplane left before harvest. The en-mass planting season got started earlier than normal and statewide progress was likely the earliest on record. The same applied to soybeans. Then a two weeks’ cold spell arrived and a high % of those acres that had emerged were at great risk of being nailed by several nights of subfreezing temperatures and the two week long cold spell. The prolonged cold soils forced that plants to become self-sufficient either before they were physiological capable of it or before their biological population had populated their root systems.

That means the plants stalled out for two weeks where they added almost no growth and turned several shades of yellow. The corn growers who had used different biological mixes or even cobalt based biological stimulants saw less or even none of that problem. Remember that when you provide the right product (s) your good bugs can colonize the root before the pathogenic ones are able to. Expect to see new products to be commercialized that provide the food to sustain the existing or newly introduced biologicals. They could include the bugs and food in a premixed form.

Many days in June were above normal in temp and the plants added 4 feet in growth in about 10 to 14 days. The plants in most fields caught up in growth and appear to be on schedule to tassel and pollinated in the July 10 to 15 time frame. We are hoping that moisture arrives before that time to eliminate or lessen any stress that could occur in these pineappling fields.

Corn stress has been seen in corn fields already in fields in central, west central and southwest Iowa as many of the incoming fronts seem to have split and moved either south or north of their regular paths. Back in 1983 there were several hybrids that would delay their silking and pollen shed until it had rained, expecting rani to come within a few days. Then after it had not rained for several weeks the plants were in a much worse situation, and the delayed type hybrids were the most affected if they had delayed those reproduction processes.

The evaluation of the 2020 in cropping conditions in Iowa is favorable, and this is true, but the topic of some degree of drought occurring in Iowa is real. A few weather observers in Feb and March were reading the weather cycles and were predicting some degree of drought in IA. With temps in the high 80 to upper 90s the lack of moisture for another week or two could be very damaging.

One thing I have noticed is that the corn stalks in many fields grew too fast and plants can break off with a slight touch. This could be a serious problem if and when we have a wind event. The plants have to accumulate enough silicon to add stalk strength.

Until now there have been very few signs of any disease symptoms in corn or bean fields. Nutrient sufficient plants have a high level of immune function and can ward off most diseases. If Mn levels are where they should be they can ward off diseases by allowing the Mn to preventing infection pegs from penetrating deeper into the leaves of stalk. Typically, disease lesions begin to appear in corn close time wise to the pollination process.

The one disease that may need to be on more corn producers watch list is Tar Spot. It looks just like its name suggests, a black spot that looks like it was airbrushed onto the leaves. The 3 way carbox-amide fungicides received the best ratings in the U of Wis. screening they conducted in 2018 and 2019. Applying the systemic 3-way mixes early in the disease cycle has done the most good in terms of yield.

The second generation of the ECB typically starts appearing in mid-June. Other adult insect emergence dates can be tracked using light tramp cates from the UNL figures from their Concord and Blair research farms. Unfortunately, no one is running the trap this season.

Soybeans

Most of the earlier planting beans have now begun to bloom. June 21 is the normal date for it to happen. Last season many varieties were a month behind in flowering and it showed at harvest.

In my travels I have been watching for fields showing signs of Dicamba particle or vapor drift. I did not have to travel far to see mile to severe crimping of the plants and leaves. During the two week period after many of the small broadleaf weeds appeared the winds were 15+ most days and the temps (85 F) and humidity levels were ideal for air inversions to occur. The Behrens and Lueschens study gave guidance on how to correlate stage of growth and rates to final yield loss.

One grower asked if the seed companies who built a portion of their sales promotion on scaring growers into planting Extend Beans because all their neighbors did, could be charged with extortion; On the 4 th I got into a bean field that had been sprayed with a Dicamba product mix. There were many 4 to 6” plants that appeared to have twisted a bit, but survived and will be growing again. I have also seen fields where the 2, 4- D results were less than impressive and a second trip will be needed to clean it up. Because the plants are flowering and the July 1 st date cutoff date for Flexstar been reached, the cultivator was discussed will likely be used. There is much more that can be applied if the other method of weed control haven’t worked.

Several companies released came out with new three day product mixes that included the new systemic and longer residual products. The carboxamides, being newer and better, are showing up in several labeled products and touted as offering longer lasting residual.

I have had a few bean growers inquire if Impulse could still be applied to flowering beans. After looking at a number of fields where it was applied I was very impressed with the additional branches and much larger diameter stems. If all of those extra branches form pods, which they should, I would recommend it on any mid maturity or later soybeans yet. There is also value in the product mix denying fungal growth throughout the season.

Persistent Nematodes

We pursued Elson Fields and did discuss with him about using his nematodes in field or two where they had serious problems with CRW. We along with several companies had requests to him in time to get the designed plots planted. We thought we were all set to receive the flask with the population of EPN in them that would then forever eat CRW larvae and their eggs. We never received them or any word on what happened except, that there may be one or several plots with a seed company or with a university researcher. In the communication details he was concerned they might escape and keep controlling corn rootworms in the field for years. Egads!

Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com.