Despite June typically being one of the wettest months of the year, it is ending to be much drier than normal across much of the state. Besides drier conditions, other common issues showing up in Iowa crop fields include weed management concerns, herbicide drift, nutrient deficiencies, and insects such as Japanese beetles and thistle caterpillars.
Iowa State University Extension and Outreach field agronomists provided the following quick update on what's happening in their respected regions around the state. These reports were gathered by ISU Extension field agronomist Rebecca Vittetoe, as her colleagues around the state sent her their observations as of June 27.
Joel DeJong: The newest drought monitor does a pretty good job of letting you know what is happening in northwest Iowa. Much of the northwest corner is well below normal for rainfall in the past 30 days — during the month of June, when we normally average the highest amount of precipitation for the year. There are actually a few fields where soybeans are still laying in dry soil and others where corn roots aren’t getting established deep enough to get into the subsoil moisture that is still present. But most fields are hanging in there quite well and would benefit from a good rain. Herbicide applications have been pretty timely since almost every day is dry enough to get into the field. Soybeans are beginning to bloom. Otherwise, no major trends in crop problems at this point in time.
Paul Kassel: Crop conditions continue to look good across my area. Scattered rainfall occurred last week. However, most of my area has had a scant 1 to 2 inches of rainfall since June 1, which is almost 3 inches below normal for some locations. This is one of the driest Junes in recent memory for many farmers. The dry weather has not caused any problems so far — with one major exception. The soybean fields that were planted May 26 to June 1 have had some real stand establishment problems. Some of that late soybean crop has emerged recently, while some of it dried out before emergence.
Early May planted corn is in the V11 stage and the mid-May planted soybean crop is in the V3 stage. Useful to Usable predicts a 103-day corn hybrid that was planted on May 7 near Spencer will silk on July 25, which is five days behind normal. Farmers are completing postemergence application of herbicides to soybean fields. Waterhemp, giant ragweed and marestail are the most common weeds in soybean fields that farmers need to manage."
Angie Rieck-Hinz: We have corn from V5 to V11 and soybeans from V2 to R1. I’ve found a few soybean aphids but nothing that warrants treatment. I’ve had nearly weekly hail calls from scattered hail across north-central Iowa in multiple events. Some hail damage was severe enough to completely destroy the crop. But most hail events left corn tattered and beans with various degrees of damage from dead to shooting new axillary buds.
… Rain continues to be extremely spotty. The far western area of my territory, northwest Calhoun County, is the driest area. And while the Eldora area had been the driest, it is now on only 1.84 inches behind average rainfall for June 1-26. Field calls the past week included some herbicide drift complaints, herbicide injury, continued calls on rootless corn and a few calls on Palmer amaranth identification.
Terry Basol: As far as crops go, corn is looking good in this area, ranging from V6 to V8. Soybeans are about V1 to V4, with many of the acres getting sprayed with the first post-herbicide application this week. According to the Iowa Mesonet, we received 1.85 inches of rain last week between the dates of June 18 and June 25 here at the Northeast Iowa Research and Demonstration Farm. The second cutting of hay is also underway or will soon begin for this area of northeast Iowa.
Mark Johnson: Overall, much of the corn and soybeans look very good considering the environmental conditions. The fields planted into less-than-ideal conditions or spots of fields that were too wet at planting are still looking less than ideal. I saw R1 soybean fields early to midweek last week [June 19-23]. I went on several hail calls. Some of the fields I visited had small stand loss, but most had very little stand loss and will come out of it without severe yield loss. In some of the fields, when splitting stalks vertically down through the nodal roots, there are areas of brown, indicating stalk rot and root rot (both diseases) has begun and may spread later if there is stress at kernel fill time.
Southeast and South Central
Rebecca Vittetoe: Some of my counties received some much needed rain and others missed out on the rain. Southeast Iowa did appear on the U.S. Drought monitor last week [June 19-23] as being "abnormally dry." Corn, soybeans, pastures and alfalfa could also use a good shot of rain. Most corn is V10 to V12 and soybeans range from replanted to R1. Most alfalfa fields are ready for the second cutting. Oats are starting to head out, and the few wheat fields in the area are getting close to harvest. Common issues from this past week [June 19-23] included hail damage to crops, soil compaction issues, potassium deficiency showing up in cornfields, thistle caterpillar in soybeans and weed control concerns."
Meaghan Anderson: Most areas of east-central Iowa received a half-inch of rain in the last week, but we're still at least 2 inches below the climate average in most areas. In fact, most of this part of the state is showing up on the drought monitor as abnormally dry now. Corn is mostly in the V10 to V13 range, while soybeans range from just replanted to R1. With rains expected this week, farmers are quickly finishing up herbicide applications before they're rained out of the fields.
As far as weed control is concerned, marestail (Conyza canadensis) continues to plague some fields above soybeans. Now is a great time to dig some roots and check for corn rootworm feeding, especially in continuous corn. It's also a good time to keep an eye out for Palmer amaranth while scouting.
Virgil Schmitt: Most of the area received between 0.5 and 1.5 inches of rain. Several small hailstorms occurred. … A severe hailstorm about 2 to 3 miles wide and 6 miles long hit west of Muscatine on June 17. As of June 27, oats are heading out and harvest of the second cutting of hay has begun. Corn is mostly V10 to V12 growth stage and soybeans are V4 to R1. Hail, lack of weed control, herbicide injury, sulfur and potassium deficiencies were common issues last week. So were Japanese beetles. It was noted that Japanese beetles really liked the new growth of the crops.
For a map showing the amount of rain for the year so far, or for a map showing rainfall totals for Iowa over the last week, go to weather.gov.