I am writing this on Sunday May 7th, so things that may be apparent later in the week remain an unknown by Sunday morning. Here goes:
In Television Land over the last fifty years, we have seen many game shows where participants are asked to use their instinct or luck to guess what will happen in the near future or what is behind Door #1 thru Door #3. Depending on a person’s age they likely watched the Art Linkletter, Queen for a Day, or the Monte and Arsenio Hall game shows where contestants do their best to peer into the future to guess the correct door will open the top prize or gift. In the crop raising world we have a similar situation where we experienced another planting season where we had an early ten-day period in early April with unseasonable warm weather and warm soils and aggressive growers responded by getting their first acres in the ground. Then the field conditions reversed as two weeks of unseasonably cold conditions arrived. Should they have jumped at the start of the 10 to 14 days of warm weather or waited until later when the soils finally warmed again in the first week of May? Will they have acceptable, good or excellent stands of corn and soy beans? Or will those early planted fields contain such low populations that replanting will have to be done. Over this next week it appears that the 70+ degree temps with sunny conditions will prevail and give the still to emerge seedings the energy they need to push their way above ground and turn the fields and rolling lands green again.
It is often tempting to try to carve out those few days in the spring where it was possible to get a head start on the season and beat the neighbors to the field. We all would like to get started early in case another 1991 or similar wet spring occurs where long planting delays were the rule. That must be why old sages say patience is a virtue. Getting a perfect corn or bean stand is more likely to occur once the soil temps stay above 50 degrees in the latter days of late April rather than in the first week of April. Soil types, percentage of fields tiled, amount of sunny vs cloudy conditions, planter capacity and acres needing to be done, soil preparations planned and work force available all help determine all play roles in when grower would like to start and need to get started in the spring. Nowadays with 16 to 24 high speed, center fill planters very common it does not take long to get the seeds in the ground.
Here is hoping that you begin to see the types of populations you were hoping for as the small plants begin to emerge. It was possible late last week to begin to spot the rows driving slowly by. Once the fields dry most growers will be making treks thru the fields and trying to reach the low areas where the soil temperatures tend to stay lower. By Friday there were corn fields where the lack of heat left plants starting to have a difficult time pushing thru the weak crust and appearing to begin leafing out underneath the soil. A half inch of rain was going to be enough to soften the ground, and that is what happened.
There are currently reports of a several major areas in the eastern cornbelt where subfreezing conditions killed the small bean plants and replanting is a must. The occurrence of several freezing nights over a fairly wide area north of I-80 and even north of I-70 was predicted by meteorologists Eric Snodgrass and Atkins. Both have been saying that the near record number of major solar flares is going to give us more erratic weather with tight isobars meaning winder days. If a person is observant of nature and has been in the past few weeks a few things stand out. The dandelions began to appear two to three weeks ago. So the soil temps are back above 50 again, but not by much due to limited sunshine. Two to three cutting from asparagus beds have been possible. The rhubarb plants are up but not enough to cut leaves off already. Give those plants another week or two. And on the home front, the red oaks have leaves expanding in size. The pin oaks are just beginning to form leaves. The Kentucky coffee tree, the Catalpa and now the 35 ft tall pecan trees are just beginning to enlarge their buds. Until the last few days it was difficult to tell if they had survived the winter.
One observation I have to ask a dendrologist about is why, after many days of polar air that dropped multiple nighttime temps below -21 F, are the nine peach trees showing the most flowering I have ever seen. In the past the minus 21 F was the stated rule of when bud tissue was destroyed. Why might it be different this year? Is nature in central Iowa getting fooled for some reason in central Iowa? Any guesses.
Counting Stands
After the ground dries from the Sunday showers, it will be time to start walking fields to see how the plant stands are and see what % of the seeds germinated and produced a healthy seedling. Conditions then may have dried enough to allow foot traffic. If the soils have not dried sufficiently try again on Wed or Thursday. At as early date in May a person would want a near perfect stand. When making stand evaluations, also make note of seed placement depth as that can affect final brace root numbers and overall crop performance. While you are digging look for signs of insect feeding on the kernel. The primarily culprits now would be wireworms and seed corn maggots. The maggots are the juvenile form of a small, slow flying fly. There are no products labeled as effective against those two pests. At planting time, the new essential oil based Big Shot would be worth trying with an in-furrow application.
One other insect that can cause stand problems or deformed corn plants to form are stink bugs. These triangular shaped insects can chew holes into the central core of the vascular system while also releasing an enzyme that continues to digest stalk material. Those plants tend to form additional suckers which end up being non-productive. Wet fields with lots of residue are those most affected by this insect.
In most springs our strong winds originated from the south and they can carry in different moth species. All but one day of our winds came from a northerly directions. As the date advances and the winds switch directions, we will see moths originate from southerly locations and our normal assortment of cutworm moths will migrate in and search for fields with a green cover or weed crop.
In Iowa the insects reported so far seed corn maggots, alfalfa weevils and bean leaf beetles. The maggots are larvae of a smaller, slow flying fly with the eggs laid on decaying organic matter. The weevils overwinter in fields and under plant debris. The greenish yellow larvae skeletonize alfalfa leaves. If they reach high populations they can greatly reduce yields and quality. The SB beetles overwinter in CRP tall grass fields, and plant residue and in larger treed areas. It is the earliest emerging fields that attract the beetles. There are typically two full generations per season.
GDU Accumulation
A few of the weather recording stations make note of sunshine hours along with heat accumulations. We saw that during the late winter time period a high percent of the days were lacking in sunlight. One other thing that can also help identify time periods most beneficial to plant growth that was talked about during their crop management sessions was tracking the hours of heat each day, rather than averaging the low temps above 50 F and the high temp below 86. Not much came of the plan, but it better placed a higher value on the longer days of June, July and August and the value of hours of heat.
Disease Suppressive Soils
The topic of disease suppressive soils soil is explained as having soils which have been treated such that the biology of the soil is more active with friendly microbial species such that serious pathogen populations are greatly suppressed by the beneficial species in the soil. The recently retired Joe Kloepper devoted the latter portion of his career to exploring this interesting topic. John Kempf and Dr. Mike McNeill cut a good podcast on the topic a year ago in recent seasons. In it they provided facts about what steps and practices can help their fields and microbial populations can help serious soil pests including soil pathogens under control without using any harsh products. The steps can include altering the soil, including a legume or sulfur rich cover crop which when tilled into the soil gasses the pathogen.
UNL Results from Optically Equipped Smart Sprayer
The first of the two U.S built optically controlled smart sprayers were put to the test in veggie fields in Arizona in Feb of 2022. Later they were moved to a location west of Lincoln, NE. A team of engineers from the UNL Ag Research Division observed the applications, studied the results and came to certain conclusions. The dual tanked, double plumbed-double nozzled spray boom was tested in corn fields to see how it compared to a regular high clearance sprayer in post plant applications. They found a reduction in broadleaf herbicides used of 87%. In preplant/pre-emerge burn down applications the broadleaf herbicide use was reduced by 94%. This study was printed in an 8/26-2022 issue of Progressive Farmer. The product savings in the trial amounted to $65.20 per acre in corn. Several other well known ag companies do not intend to be left in the dust in this arena. At least one of these companies only has the desire to sell you one of their fully equipped boom and the electronics that come with it. You would then mount the equipped boom on the sprayer you already own. Vital to such equipment are over 1 X 10 to the 25th power data points used by the AI to differentiate between all the weeds and all the crops.
Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com