Recent rains were a welcomed event in some areas while other areas hoped that it would hold off for a while. This is because the areas to the south have been classified as abnormally dry to a moderate drought while the areas to the north have been excessively wet all spring.
Planting is winding down in the dry areas and a few more days will finish both corn and soybeans. The soil worked up like a garden south of Highway 20 and some crusting occurred from rains that fell in early May. In most years, this crust would not have been an issue but the vigor of the corn seems to be slower than normal this season resulting in some situations where rotary hoeing was recommended. I have no explanation for slower early season growth but I wonder if the soil temperatures lower in the soil profile are cooler than normal because of the lack of spring rainfall. The upper four-inch temperatures would warm quickly but they would also cool just as quick when a cold front came through. Recent rains have helped with the crusting of the soil and plant stands look good overall except for areas that had excessive rainfall and ponding.
The area to the north of Highway 3 area is struggling to get the crop in the ground. Late heavy snows and frequent rains have limited the number of days that producers have had to plant corn or beans. Some areas corn plantings are as low as 5% planted up to 35 to 40% planted depending on soil conditions and rainfall.
The main question has been on if farmers should switch to earlier maturity hybrids. We have been recommending that they stay with the normal maturity hybrids for their area until at least May 25th because they have done the best in the past under similar situations. Early hybrids are an option but past experience has shown that they do better when kept in zone and their southern movement is limited. If the season turns to normal or above normal heat, adapted hybrids will be best. Producers that have some late hybrids in their planting intentions have been recommended to switch to different hybrids unless they have a need for high moisture corn or have the ability to dry it. Studies have shown that hybrids have the ability to mature with less Growing Degree Units at the rate of 5 GDU’s per day past the prime planting date to a total of 125 to 130 GDU’s in one season. In many cases, this is close to the equivalent of the growing degree units that have accumulated since May 1.
As farmers scout their fields for final plant stands, they should keep an eye out for insect feeding from black cutworms, true armyworms and seedcorn maggots. This is especially important for farmers that have planted corn into cover crops. The termination of these crops was slow because of cool weather or the inability to apply the herbicides and many producers did not have time to allow 10 to 14 days between termination and planting. Trappings have been sporadic across Iowa and scouting is the best way to determine if there is a problem in the field.
Hopefully the weather cooperates for the farmers in our northern area and we can finish the plantings of 2018 soon. Please be safe and let us know if you have questions.
Note: The information in this issue is based upon field observations and third party information. Since variations in local conditions may affect the information and suggestions contained in this issue, LG Seeds disclaims legal responsibility therefore. Always read and follow label instructions.
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