We are now into late May and the planting season is in all stages of completion. The first corn and beans in Iowa and surrounding states were planted during the first 10 days of April when soil temps remained cool with forecasts for colder weather ahead. It was a “would I or should I take the risk of planting when the calendar says it’s time, or be more cautious and wait until warmer conditions are here to stay?”

Then the 10 or 15 days of rain arrived and most operators and their equipment had to sit on the sidelines chomping at the bit, figuring out which of their fields were the driest and taking advantage of any planting windows that occurred. Finally, around May 15, just as most operators’ thoughts drifted toward lower yields and perhaps having to switch to earlier varieties of corn hybrids and the hassles involved, we were blessed with a nice five to seven days of warmer and drier conditions.

It was easy to expect that most operators would run longer hours all of those days, and they did. It would be interesting to be able to find out how many hours were put on their tractors across the state during this period. With Sunday’s rain, field work will be put on hold for a few days.

Then it will be time to start scouting fields and corn stands to decide if their plant stands are adequate or not, then if which or any of the ponds need to be replanted. With this being the first spring when we have gotten much spring moisture since 2020, we have to realize that weather delays have always been the norm. After most regions of the state endured D1 through D3 drought conditions during the 2020 through 2023 growing seasons, not many growers are hoping it would quit raining.

By now the field scouting trips seem to be showing some of the corn stands in the fields planted in the one or two days before the cold rain during 10 days in late April. There will be a few of those that may be torn up and replanted if time and conditions permit. If that happens, getting all the acres planted for the first time is the primary goal of most farmers. We often saw in 2023 that the top corn yields were those from fields planted in the May 10-20 time frame. Picking the optimum planting window is always an inexact science. The main rule is to wait with planting until the ground is fit so as to not cause compaction with machinery traffic.

In time, we have to see how to correct the seed quality issue, which was written about by Ken Ferrie, an Illinois consultant. He had advised a number of his clients to collect a few pounds of their major hybrids and send them to qualified seed labs for cold germ and seed quality tests. This has been done with clients of another planting guru in our state.

Planting progress

The NASS statistics will be released again on Monday. They will likely show that corn planting progress in the Midwest will be in the 90-plus percent range and soybeans at 60 percent or better. These percentages indicate that trendline yields or better can be forecast and can be achieved, but the crop still has to endure and thrive through September without major problems. Having more moisture and the presence of inoculum can create conditions favorable to root diseases early and foliar diseases in the later V stages. Meanwhile August and September are predicted to be hot and dry in the Midwest.

The South American countries of Argentina and Brazil are having problems with intense heat and erratic rainfall patterns. The last two seasons have been incredibly tough with intense heat (114 degrees F) and very erratic rainfall. This includes intense heat with long stretches of 100-plus degree temps. Huge rainfall events have caused massive flooding that destroyed crops and wiped out rural villages. This is real, with at least one company moving a portion of the South American sorghum seed production to Nebraska.

Grain sorghum

That crop seems to be poised for a revival. It has always been known for its ability to survive dry weather and tolerate intense heat. Thus, where it has been too hot and too dry for great corn yields as in states to our west in 2022 and 2023, producers in Kansas, Nebraska and South Dakota there are producers who have pondered an increase in milo acres. The same goes for areas where aquifers are being depleted. Typically, it commanded a lower price than for corn grain. That has changed in recent years as it is still non-GMO, thus carrying an advantage for countries where livestock feeders seek such grain. Mexico imports lots of it as a feed grain. Its use as a flour source is being studied more as it doesn’t cause gluten problems.

Weed issues

A good Corteva site provides daily GDU accumulation and a timetable of weeds which will be germinating and emerging at each interval. At most Midwestern sites, the No. 1 weed are members of the pigweed family. Once you see these plants merge and they reach 2 to 4 inches they can become difficult to control. Every trip through the field with the sprayer has to be dedicated to eliminating every one of them. Currently, cooler temps seem to have helped keep Palmer amaranth from spreading.

There was no release of any new landmark herbicide for 2024, as in the 1980s when there were many more companies and their discovery groups. Thus, any new advertised product is a combination of previously labeled products from different families and modes of action. A good residual product, or post products offering long residuals, are the basis for successful mixtures. The expensive cost for developing, testing and registering new herbicides is limiting even for the larger firms. If those firms have a pharm arm, the chance of securing funding for ag use is decreased in favor of pharma.

Perennial weed control

Every season, the tougher-to-control perennials seem to spread in fields where more acres are affected. Ones on the list are hemp dogbane, Canadian thistles and scouring rush. Attempts to control these should be made when the field is planted to corn — spot spraying them with members of the Pyridine originally from Dow such as Stinger (Chlorpyralid) and or Trichlopyr. Several candidates They each control broadleaves.

There is an Arkansas company called Grassworks that builds weed rollers from 15- to 50-foot widths, which has a hydraulically driven, counter clockwise rotating steel drum covered with a carpet that wipes your herbicide of choice on the underside of the leaves of weeds taller than the crop. A pressurized reservoir automatically delivers the liquid mix to the carpet. There are no nozzles or drift to harm non-target crops. If needed, it could eliminate taller waterhemp after they poke above the canopy.

Soybean planting and articles

Lots of bean acres have been planted in the last five to six days. With the ground temperatures across Iowa now being above 60 degrees Fahrenheit most should germinate and emerge quickly. We need to have heat, but no pounding rain.

Many articles have been written about planting beans before planting corn in the hope of getting more podded nodes on the main stem. The window to plant early did not happen, thus the chance to form additional podded nodes on the main stem via early planting is gone. What other method or microbe can be used to form more branches on the main stem?

This can be done with multiple applications of a manufactured cytokinin foliar product. These are available, but have a short residual in sunlight. The alternative program would be to apply a hormone-producing bacteria to the plants where they will populate the leaf surface at the V3 to V5 growth stage and you will see additional branches form. We like to see BranchOut partnered with an energized sugar mix (Micro Boost) and foliar nutrition mix called Foliar Blend. This last product contains cobalt, which will stimulate the bacteria to hyperactivate. You can contact Larry at Agronomy Rx (515-571-7269) or Marv Mortensen (515-370-3381) for details. We often see an additional four to five or more additional branches to form and have seen as many as 14. With the additional branches come additional flowers and pods to form, increasing yield potential. These are not a silver bullet, but a very affordable tool in a systems approach.

When I was 7 or 8 years old and working in our big family garden I saw something strange. This 3- or 4-inch white worm suddenly corkscrewed out of the ground in front of me. It was about as thick as a piece of thread. It was no night crawler or earthworm. I had not seen any of the same thing since. At Iowa State, I took the two nematology classes, Entomology 594 and 694 taught by Don Norton. It involved lots of reading and memorizing lots of strange names with two classes per week plus a three-hour lab. We learned about the many different classes and families of nematodes that caused problems in plants.

Where this fits is that I received an email from a consulting colleague in northeast Iowa who has been scouting several fields of emerging no-tilled soybeans and digging up sprouted soybeans where the cotyledons were browning and being devoured by a sizeable population of similar long skinny worms. To get verification, I sent the letter and pictures to a mineral/microbe specialist in Utah and to an entomologist who runs an insect research lab in Florida. Tom Dykstra was the prize grad student of Phil Calahan, a University of Florida entomology professor. Calahan’s background was first with the Irish Air Force during World War II, tasked with conceptualizing, designing and building radar antenna. After college he got his entomology degrees and began his research work, starting a completely new arena of the electromagnetics of insect sensory systems and their role in navigation abilities and food sourcing. His ideas and mind were beyond that of his colleagues. His work was used by the U.S. Air Force in developing stealth technology and the applications to modern radar.

Dykstra verified that these were indeed saprophytic nematodes who were eating low energy, chemically treated, no-tilled soybean seedlings. I passed this verdict to my colleague along with three PowerPoint presentations, which he had used at a January conference in Idaho. Dykstra’s explanation used his data about plant energies and attractiveness to predators and means to avoid future problems. Only time will tell if this is a one-time occurrence or will become common. We will try to post Dykstra’s PowerPoints for interested crop people.