Hurricane Harvey and Irma pounded Texas last September with seven to ten days of heavy rains. Much of the Midwest didn’t have a declared hurricane, but when a person looked at the weather map beginning a week ago the forecast for about a week’s worth of rain seemed to be a strong possibility. Around central Iowa the reality hit on Saturday when the ISU football game got rained or lightninged out. On the map the area receiving rain stretched from down into old Mexico up into the Nova Scotia province. Areas that had been shut out of substantial rains received major amounts, enough to realize their moisture profiles could actually get filled up again before the 2019 planting season rolls around. The major thoughts had to be ‘Wished it would have come a month earlier.’ It may help fill the bean pods, but as far as the corn goes is that it could lead to standability issues as stalk rots were already very common and stalks in the dry areas have already hollowed out.
Stalk Lodging
Even before the heavy rains arrived there had been a few windstorms that caused significant lodging, where the stalks did not break off, but literally bent over without snapping. Time will tell what the end results will be, but a slow and muddy fall harvest may be the story in parts of SE Iowa and NE Missouri.
Most growers could benefit from making a quick trip around their fields and going in to perform a stalk strength test in each variety to see if the stalks are getting soft. From the news that I have heard the operators who do not have some sort of reel for their machines are checking for their availability if the need arises. There are various models with the ones that can fold away or up if they are not needed rather than having to be mounted before heading into lodged fields saves time and effort. In one conversation with a SE Iowa grower the topic of a corn reel that was manufactures down Dimmit, Texas that had gathering chains running on every snout was discussed. I don’t know if they are still available. They were typically used when there had been a major infestation with the Southwest Corn borer. Doing a quick net search I could find no mention of them since my 2011 article on the topic. With today’s poly head and the newer Yield 360 brushes for inserting into the gather chains they should be easier to use and faster.
Last weeks’ rains and the cooler conditions changed the appearance of most of the fields that still had some green in them. Those that died three to five weeks ago had weakened stalks already. Charlie Hurburgh in his presentation at the Farm Progress Show was advising growers to start harvesting when the grain moisture got down to 30%. With today’s prices that creates a real conundrum in that minimizing drying cost seems most important to farmers who don’t thousands of acres to harvest. Hopefully the forecast dry conditions return and stay for a few months.
As to the condition of the corn crop in each state, not much has changed in recent surveys. The % of the crop rated good to excellent remains higher than most would give it. In the Illinois survey done on Sept 2nd they stated that 36% had matured. They were likely ahead of us in that category. So if the plants in the surveyed fields were around 25 to 30% mature, why were about 75% of the fields dead?
Hot Topics
The Farm Progress Show is in recent history and the same amount of planning, preparation and expense went into it as in previous shows. Every farmers’ budgets still remain very tight until the tariff squabbles are resolved, so there were not many pre-orders or reservations made during the show.
The Next Tasks
Tight budgets likely mean that the amount of dry fertilizer applied this fall could drop even more, depending on how closely each operator is monitoring the nutrient levels in each field. That means that everyone should still maintain a good soil sampling and nutrient analysis within their operation so they can make the best decisions about how to manage each field’s specific fertility needs. The focus needs to be on fertilizer efficiencies, which could refer to the use of stabilizers, placement with the newer planter or strip till attachments, or making use of more foliar applications. It can also take the form of using polymers and stabilizers or boosting the soil microbial life to increase the availability each nutrient. There are several N stabilizers and several products like Avail that keep the P from getting tied up by the Ca and Mg in the soil profile.
In soil tests I continue to look at to help a grower interpret them I like to see the difference between the P1 and P2 levels. Typically if there is more than a 25% difference between the two, and the P2 level is in the 35 PPM level the need for additional P to be applied is minimal. It typically requires a microbial mix where the Pseudomonas fl population is restored and the same is done to restore decent O2 levels in the soil via improved drainage, a deep ripping operations, or a strong gypsum application is made.
Other suggestions worth mentioning would be to ask the analytical lab for a more complete analysis. Include the Micronutrient package to include Mn, Zn, Bo, and S. Also consider testing a few representative fields using the Haney methodology. Those fields with levels in the double digits will have higher yield potential even if their nutrient levels test on the medium or low side of medium.
Since the effectiveness of the Fayette source of SCN resistance has been found to be less effective it may be helpful to pull a few soil samples from fields that have shown the common symptoms. These could be analyzed to determine whether or not the populations represent a threat to bean yields. In previous years there were few products that could be used to protect the plants and reduce the SCN populations. In 2019 there are now four or five products that are EPA registered products for SCN control.
Gall Midges in Soybeans
This summer was one where the tiny maggots of the Midge flies were found in bean fields in the NW corner of the bean belt. That includes IA, NE, SD and MN. There supposedly over 1,000 different species of flies with the one we know the most about being the Hessian flies that supposedly snuck in the Hessian settlers who came here from Eastern Europe who brought infested wheat seed with them.
Those flies and their maggots which tunnel up the stalk, causing the stems to collapse, have become an annual issue, which wheat farmers counteract by not planting until the fly free date for their respective areas has been reached on the calendar.
There will likely be a joint effort on the part of the entomologists from the ISU, MN, SD, NE, KS and likely ND in a quest to learn more about their biology, figure out if their feeding habit and overwintering ability have changed, document if any yield losses are occurring, see what if any treatment thresholds have been established where any other midge infestations have occurred, then what if any control measures might need to be established
The one insect that many expected to become an increasingly important insect pest of soybeans is still the Dectes stem borer, because of their long egg laying period and the severity of their feeding damage. While they are conducting their studies it may be wise to be monitoring the plants’ nutrient status in case something is increasing the plants’ attractiveness, as was seen by Dr Reginald Painter of KSU when the sorghum aphid changed their biology back in the mid 50s.
A minor insect here that rarely gets mentioned are the thrips. They are the small cigar shaped sap suckers that live on the underside of the soybean leaves. At high numbers they can affect yields in a similar fashion as do aphids. In the last bad Argentine drought the bottom sides of the leaves were greatly by the sap loss to the thrips that had become resistant to the small pests.
One More Try
We had a huge crowd at the Aug 20th meeting down at the Guthrie Center facility. The attendees expected to hear the list of great speaker, who were willing to share their knowledge. They also wanted to see the corn they have been hearing or reading about. The heavy rains kept pouring down the entire day, keeping guests from walking the plots to see the still green and healthy corn plots. We know that many of you would still like to see the corn plots and high yield fields, so in looking at our schedules figured that us being there and able to show everybody around on Oct 1st from 9:00 AM until 3 PM would work on our part. This should give people a chance to see corn with a very high yield potential on low CSR, HEL soils in a corn on corn rotation. The site is still at 1778 Hwy 44 West, which is four miles west of Guthrie Center. Make the sun shine on that day.
Flash drives recorded at the Aug 20th field day are available thru the www.centraliowaAg.com website. The list of speakers and their presentations were well received and full of information that could help many growers in future seasons. Click HERE to get specific details.
Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com.