CROP WATCH
County Fair season is upon us. That time typically marks the midpoint of the growing season. What happens now weather-wise will determine how good or how poorly our springtime efforts and decisions are rewarded.
The corn crop
One needs to go flying to get a better handle on the state of the corn and bean crops. Those who have been up in the air numerous times say that things are dramatically over rated. They tell of too many yellow spots and drown outs that will reduce the productive acres by a significant percentage.
From up in the air a different story is told than what a ground level estimate will give.
Now that the corn plants are taller and tasseling has begun many more fields appear even and fantastic from the road. Many observers have noted the many fields and low lying areas where either enough nitrogen was volatilized to have created a shortage or the roots were in an anaerobic soil and were not picking up the applied nitrogen. The net effect will be that ear size and plant health are going to be affected.
There are going to be many fields planted on better drained soils or their topography or tiling was such that water never sat on the fields that are going to push the upper limit of their genetic yield potential. Yields of 250 Bu/A are going to be highly possible.
On the other end of the spectrum will be fields that have been stunted enough and have been short enough in nitrogen that attaining 100 Bu/A will be a challenge. What many growers and agronomists are noting that there are fields that traditionally have not had drainage problems in the past, yet are yellower than they have ever seen. Something else seems to be a factor that is at work in decreasing availability of the applied nitrogen.
Those who used nitrogen stabilizer are glad they did. Both Agro-tain and Nutri-sphere look good when applied with 28/32. So far the fields receiving 82 percent with N-Serve also look better as growers expect an economic return from the use of that product. Swine producers would like to have a product they could add to the liquid manure to fix the nitrogen to prevent its loss. One form of Instinct can be added to a slurry tank. Early trials with a specialized formulation of Nutri-Sphere look good and it could make its way into the commercial market.
In case you have not had the chance to see what 18 inches of rain in 10 days looks like and does to the crops, head to the Humboldt through Clarion areas.
Whole quarters were under water in many areas and water was still two feet deep in many fields earlier this week. The plants flashed yellow about day four, then by day seven the plants turned gray and pineappled.
This week those plants had collapsed and fell into the water. Now they are just smelly ponds that will need to be managed when and if they ever dry.
The Western bean moths are now flying. Egg masses have been few yet. Watch light trap or pheromone counts in your respective areas and be scouting.
The soybean crop
Most of the soybeans have improved the last weeks as their roots began functioning in partially aerobic soils. Nodulation seems to have occurred and the bacteria are fixing the needed nitrogen. The tallest plants have 10 nodes. Key to getting maximum yields is to get the plants to form as many branches as possible and to retain the flowers as pods.
The growers who raised the top yields, but don’t care for their names in the paper, have generally discovered a foliar program that works and have been lucky enough to get rain during August when the seeds have to fill.
They discovered how to manage the plants surrounding biology, maximized nutrient availability and manipulated each plants’ physiology. Then the rains have to cooperate.
In this week’s bean scouting the first leaf and stem diseases are appearing. Early septoria and stem anthracnose can be seen with the naked eye. It looks like the early stage of cercospora is also appearing. If it stays wet with lots of dew downey mildew and white mold are likely. Be scouting and managing for them.
With most insects appearing ahead of schedule be prepared for the first generation of bean leaf beetles. Since the overwintering beetles were here in early May the larvae have been feeding on the roots of small bean plants.
They have now pupated and will soon emerge with the intent to consume leaf tissue in the same or neighboring fields. Aphids are in Minnesota and Wisconsin but population buildup has been slow. We will have to make decisions about treating for them in one to two weeks as the last pass is being made.
The long hours of leaf wetness and high levels of inoculums will make many fields susceptible to leaf diseases. Be observant of those small yellowing specks on the leaves of your corn plants.
That is when those diseases can increase dramatically. Review the disease ratings of the hybrids you have planted and take the appropriate action.
If you can do so send in tissue samples for nutrient analysis to see how the nutrient levels stack up versus known standards.
Deficient plants are the ones more likely to have disease problems. Though no one wants to spend additional dollars on fungicides now, you also should want to protect the yield potential that exists. If you do want to use a fungicide know the appropriate timing to use and what surfactants are most likely to lengthen the protective period as well as what product or mixture is going to give the best results. It’s your money.