Soybean Aphid
Soybean aphid risks will be on the increase both in area and also in risk level as we head through this week and into next weekend. With soybeans into the reproductive stages in many areas, growers located north of I-80, but especially along/north of I-90, should regularly scout fields and take note of population dynamics. Overall cooler weather is predicted in the next week or so with generally less rainfall (especially across the northern soybean area), and this will be favorable for soybean aphids to increase in population. Low risks extend from roughly I-80 in east/northeast Nebraska and central/northern Iowa north into the eastern Dakotas, Minnesota, and Wisconsin. Low risks have also been introduced to the forecast by late week into next weekend across lower Michigan and into southern Ontario, Canada. Given the weather outlook and crop stage, a Moderate soybean aphid risk has also been added to fields across central and west central Minnesota into northeast South Dakota and far southeast North Dakota. Populations can change quickly, and any decisions to treat should be based on if economic thresholds are being met/exceeded and most importantly, what is occurring in specific fields versus a general local/regional report as populations will vary even across adjacent fields.