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The week of May 11 – May 17, 2025 was another relatively quieter week for both black cutworm and true armyworm moth across the state.

A total of 33 black cutworm (BCW) moths were reported last week, with no significant flights being reported. As a reminder, now is the time to be scouting for black cutworm based on our predicted cutting dates from significant flights from earlier this spring combined with growing degree days. 

During the past two weeks, temperatures across the state have been warmer than normal, as much as 0-8 degrees above average. Northwest Iowa has had the largest departure from normal during this time period. Spotty precipitation has fallen across the state in the past 14 days, with southeast Iowa receiving the largest amounts at around 1 inch. Despite that, the entire state is below average for precipitation during the last 14 days.

You won’t want to miss any of the upcoming field days hosted at the outlying Iowa State University Research Farms this summer. These field days will feature the latest information on crop production and management practices. Below is a list of the upcoming field days that will take place as well as what topics will be featured at each field day. All field days are of no cost to attendees and open to the public.

Each year brings fresh concerns related to herbicide performance and the weather. We can’t control the weather, and we are often at the mercy of wind, temperature, and moisture whether there is too much, too little, or ideally, just right. A recurring concern this spring has been dry weather and how it impacts herbicides. 

This last week (April 27 – May 3, 2025) was a another relatively active week for moth activity across the state for both black cutworm and true armyworm moths. 

A total of 107 black cutworm (BCW) moths were reported last week. Three reports included significant flights: Story County (April 27), Lucas County (April 28), and Pottawattamie County (April 29). 

Rain and wind has impeded getting fieldwork done this spring, but it looks like the weather forecast is heading for drier conditions. This will allow farmers to get the remaining corn and soybean fields planted across Iowa prior to when yield potential starts to drop off in mid-May. The latest USDA Crop Progress Report estimates that 34% of our corn is planted and 25% of the soybean crop is planted. 

As we are paused mid-way through spring planting season in Iowa, farmers and agronomists are closely monitoring weather conditions that will impact planting of the corn and soybean crop. This year’s planting season has some resemblance to spring 2024, with a decent planting window in early to mid-April followed by late April rain and cool temperatures. Despite these challenges, high yield potential is not lost.

Are you a crop scout, or interested in honing in on your crop scouting skills? Join us for our Crop Scout School on May 22, 2025 at the ISU Southeast Research and Demonstration Farm near Crawfordsville (3115 Louisa-Washington Rd). Check-in begins at 8:30 a.m., and the program runs from 9:00 a.m. to 3:30 p.m. 

Iowa State University Extension and Outreach Field Agronomists have completed their spring survey of subsoil moisture in northwest Iowa. Subsoil moisture sampling in Iowa dates to February 1954 when ten sites were chosen for soil moisture sampling. In 1959, the sampling increased to 22 locations, and in 1971, 61 locations were sampled. Today, 18 locations are sampled in northwest Iowa.

The last week or two has been refreshing with warmer temperatures and pastures beginning to green up. As that green flush appears, it can be tempting to turn animals out too early. However, many pastures across the state have taken a hit in recent years due to drought and/or flooding. As of October 28, 2024, much of the state was still experiencing drought conditions, with soil moisture deficits extending from the surface down to 1.5 feet (Figure 1).

To continue reading this blog, head to the climate outlook on the Natural Resources Stewardship extension page.