July typically brings a lull in soybean diseases. By this time, plants have grown out of early-season issues, and late-season diseases usually haven’t arrived yet. But every season brings its own challenges. With the frequent rains this year, some of the typical “August diseases” are starting to show up earlier than expected.
This week, we’ve already spotted a few diseases that normally appear much later in the season—sudden death syndrome (SDS) and white mold. While these diseases are never welcome, finding them in July is especially concerning.
Unfortunately, there’s not much you can do about SDS at this stage. However, you can take notes to guide future management decisions, such as variety selection and seed treatment options.
For white mold, you still have options. Scout your fields and consider applying a fungicide if conditions and risk warrant it. The following tools can help you decide:
- Crop Disease Forecasting Tool – This weather-based tool forecasts the risk for several diseases, including white mold.
- Fungicide Efficacy Tool – Quickly filter fungicide options to identify the most effective products for disease control.
- Crop Lookout – Use this interactive map to see what diseases are appearing in your county. If you see a disease that hasn’t been reported yet, please submit a report. These data help refine future disease forecasting models.
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- Professor
- Extension Plant Pathologist