I was out scouting some double crop soybeans earlier this morning and came across several fields with moderate populations of soybean aphids. I have not encountered aphid populations this high in several years. The early flowering period has been shown to be a critical time for soybean aphid damage in several Midwest studies. Impact on yield has been as high as 50% in some studies. Fortunately, the threshold for soybean aphid is fairly high, 250 aphids per plant. This threshold allows for about seven days time to allow for gathering spray materials, until populations would build to 1000 per plant. Lady bird beetles can keep low or moderate soybean aphid populations in check. More information on scouting and control can be found in the RCE soybean aphid fact sheet.
Bill Bamka
