Effectively achieving season-long control of soybean aphid requires a strategy that includes both chemical and natural control.
Independent crop consultant and soybean producer Sarah Lovas says it is time to change our thinking about how insecticides and beneficials can work together to achieve season-long pest control.
“We need to start thinking about soybean aphids differently, while taking into account what beneficials can do for us,” Lovas says.
Lovas, who operates Lovas Consulting in Hillsboro, North Dakota, also farms corn, malting barley and hard red spring wheat.
She was among the first to try Transform® WG insecticide on her farm in 2015. That year, she treated about one-third of a 190-acre soybean field with Transform. The remaining two-thirds of the field was treated with a competing herbicide and used as a check.
“That was a nasty aphid year. Soybean aphid populations began moving into fields in early July, and we sprayed the third week of July, which is very early for us,” Lovas says. “Soybean aphid is a community pest, and if we are all spraying a friendlier chemistry as a community, we can spray once and be done with it for the season.”
To better illustrate this concept, Lovas contrasts wild oats, which is not a community pest, with soybean aphid.
“Wild oat populations, generally speaking, occur in the same place in a field year after year,” she says. “In comparison, once soybean aphids are brought in by storms or move into the crop from host plants, such as buckthorn, those insect populations create an aphid epidemic. It’s a community pest because when one of us has it, it spreads to other fields in the area.”
Lovas recommends treating for soybean aphid when per-plant populations exceed 250 on 80% of the field with pest numbers increasing.
“Having increasing soybean aphid numbers on 80% of the field is very important because some years you may get a patch of aphids in a field that goes away without any insecticide treatment needed,” she says.
Because soybean aphids have documented resistance to some modes of action, Lovas says, growers need to employ both Integrated Pest Management practices and the natural control provided by beneficials.
Transform® WG insecticide targets sap-feeding insects, like soybean aphids, and is less harmful to beneficial insects. With Transform, it is possible to achieve long-lasting control of soybean aphid populations while preserving the beneficials that can save you the time and money associated with a second treatment.
“We need to knock down pests when they reach threshold, but then let the beneficials control any lingering populations,” Lovas says. “It’s crucial to let that beneficial population take off and do its thing. Once beneficial numbers increase, they can manage the remaining soybean aphids.”
Prior to using Transform, Lovas says, she would often have to spray twice each season for soybean aphids. With Transform, that second spray was not necessary. “There were a lot of lacewings, ladybugs and other beneficial insects present. You could still find some aphids, but they were way below threshold. And that population of aphids stayed in check for the remainder of the season,” she says.
Another advantage Transform offers is the targeted activity it provides to sap-feeding pests, without flaring spider mite populations.
“Spider mites are not our primary target pest, but certain insecticides will flare spider mites while eliminating the beneficials that would normally help provide control,” she says. “That’s not the case with Transform.”
Learn how Transform can put a stop to soybean aphid infestations in your soybeans.
