Temp trend risk among crops

by | Apr 30, 2019 | Crop Watch

May arrives earlier this week, even though the prospect of receiving snow in northern Iowa and in neighboring states over the weekend made it feel like late winter rather than late spring. Luckily the jet stream shifted slightly from its predicted path and snowfall amounts were less than expected. The maximum amounts that fell across S Dakota, MN, Wisc and ILL seemed to be in the 4” range. It could have been a lot more, which was not needed now.

We will have to wait until Monday morning to see the NASS figures on corn and soybean planting progress across each state and region. It was relatively dry last week so there were considerable acres planted in western and central Iowa. Wet soils in the E parts of the state kept most farmers from getting much done. The same applied to extreme N Iowa and a high % of the E Cornbelt acres. With the arrival of May, the optimum corn yield window won’t be open much longer. May 10 th is the targeted completion date to hope for now. Getting sufficient days with clear skies and drying conditions in the near future will be imperative for Midwest growers. The 10-day climate prediction models indicate cooler and wetter than normal can be expected. Larger equipment can help catch up, but not when it is sitting on the sidelines.

There were two notable events in the Ag world that could impact people and crop production. The first was the Bayer Shareholder meeting held in Bonn, Germany. On the hot seat was Herr Werner Baumann, the CEO, who was greeted with a 55% no-confidence vote by the voting blocks of the common and large shareholder groups. That typically is not indicative of a long rein at the helm.

The other was the release of a study conducted by the noted Environmental Toxicologist at Washington State, Michael K Skinner. Years ago he had tested the effect of six environmental toxins at levels as low as 1% of the rate considered dangerous. The effects of the exposure often did not show up until the third generation by upsetting the epigenetic coding in the lab animals’ DNA. This toxicology experiment involved a commonly used herbicide that he fed the lab animals and then raised thru the third generation, then studied the effect on health. In other words, your kids or grandkids could be affected by your mother’s or exposure to DDT back in the 40s and 50s. This can be viewed at this link: https://bit.ly/2WaLMOD

Cold Soil Threats

Even those growers who have had corn in the ground for a week or more are concerned about getting enough heat units to keep the seeds germinating and emerging to capture sunlight to support their growth and development. The continual cold conditions make it difficult to accumulate the GDUs needed.

There were questions from growers who were wondering if in recent years we had seen problems where sprouted or emerged seedlings had been killed by freezing temperatures in Iowa. The most recent cases were back in 2002 or 2003 where the nighttime temps in central parts of the state dropped into the mid-20s and the fast emerging hybrids planted less than 1.5” deep on sandier soils had been killed. The faster emerging hybrids had the tender part of the hypocotyls forming shallow enough that it was in the freezing zone long enough to kill cells.

Any map showing Fri or Sat night time temps across the region dropping into the mid 20 F range will give us guidance as far as where any early planted fields may have been at risk. Long Term

Temp Trend Risk among Crops

A humate/mineral specialist from Illinois who had a hand in developing the high yield plots near Baltic South Dakota last season was describing a new mixture of humates and biologicals that was increasing the soil temperature in the seed slot by 10 to 15 degrees. It will be interesting to see his results this season. If it works regularly well it may find more usage, specifically if the colder, low sunspot based Maudner minimum solar cycles predicted for the central U.S., create the cooler soils. Remember that we are in the 12-year period where the sun is switching from solar cycle 24 to 25 and sunspot activity will remain low.

In this week’s KS IPM newsletter they were giving guidance to the cotton growers in the SE part of the state where acres have increased in recent years. They mentioned the seeds/seedlings seedlings needs soil temps of 64 F for 100 hours to germinate and emerge. Because the seed soaks up 60% of the water it needs to germinate in the first 30 minutes and is very prone to cold water imbibition, stand losses are common. Once I grew a few greenhouse started cotton plants at a Webster City plot. They formed bolls but didn’t get mature enough to open.

The Fertilizer Squeeze

The earlier predictions for supply and application equipment shortages have come true in places. Guidance on how to respond has been given by advisors, but weather and equipment problems affect our ability to respond. Getting the fertilizer applied first and then planting the field is the preferred plan. If the planting date is getting later, and the optimum yield potential window is closing, and no fertilizer has been applied, then the order may have to change. Then the questions about application equipment and form of fertilizer are available should be dealt with as early as possible. Will that be the case in parts of the cornbelt this season? Does someone in your area have a high clearance rig equipped with Y-drops that does custom work? 

Alfalfa Needs

In the southern regions in the Midwest the alfalfa weevil larvae are appearing and feeding on the foliage already. Be scouting your acres as the value of alfalfa hay is very high this year. It may be the year to put out new seeding if it fits your operation and market potential.

Soybean Seeding Rates

The issue of seeding rates of soybeans has constantly been discussed over the years. Their ability to compensate for gaps in the stand is recognized, so as seed and seed treatment costs have escalated the profit potential for lower seeding rates is worth looking at. The curveball or outlier producer who illustrates this discussion best is Jimmy Fredricks of Rulo, Neb who bested Kip’s irrigated record of 153 Bu/A with a 2017 yield of 163 Bu/A. What was surprising was his seeding rates that were as low as 50,000 seeds per acre. As expected his production stories did not make it into many media publications because no seed company wants him as their poster farmer since he is only planting about half the seed count most bean growers do.

Mark Terpstra of Mark Seeds, Perry, Iowa used to have a nursery where he only left one variety and plant every four feet, allowing it to express its genetic ability maximizing its branch number. There are genetic influencers that help determine this. Wide plant spacing allows greater blue light penetration into the canopy. The plant cells use a process that may be called blue light crystallography, where they created more branching. We also see determinant varieties, as they used to grow 100% of the fields in S America, form one or two racemes at each node, with each having the potential to form 26 flowers and pods. Many of the new varieties began to show this trait two to three years ago. The other method of increasing branch number is to trip the plants’ hormone balance to being cytokine dominant. This hormone can be applied via the application of artificially produced products or the application of bacteria that are cytokine over-producers. That’s the optimum method that can be applied to any of your commonly available and grown varieties. Combined with earlier planting, yield potentials have been increased.

May the sun shine on your fields and allow you to get your spring field work done.

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