As soybean fields enter seed set throughout the state, we continue to get questions about how long to scout for soybean aphid. This year, aphid populations have been extremely variable with a limited number of fields exceeding the economic threshold (250 aphids per plant with increasing populations on 80 percent of the plants) in late July. In August, however, there have been more reports of increased aphid activity throughout the state (i.e., some fields were clean until last week). Many of the extension field agronomists also indicate winged aphids are showing up in fields. This correlates well with current aphid captures in the Regional Aphid Trapping Network (Figure 1).
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