Soybean aphid populations require continued watching. Some fields are on there second insecticide application. Others, where applications were made earlier, look good with infestations maintaining below threshold. Predators are generally very common in the fields. Some aphid mummies, indicating wasp parasite activity can be found (Figure 1). In addition, fungal parasitism of aphids, leading to their death, is finally beginning to show up. NW Minnesota continues to be a hotspot, but others are joining in the fight (Figure 2).

Many of the aphid nymphs are sporting wing buds, an indication that winged aphids are going to be very common during the next week. These winged aphids will disperse to new plants or fields in search of soybean, or perhaps some movement to buckthorn.

Soybean are in the R3 to R5 growth stages. For a review of growth stage descriptions and management decisions associated with them, click here.