News

Fewer aphid infestations in Minnesota soybeans this year

An integrated pest management specialist at the University of Minnesota says soybean aphid infestations are spotty statewide and less than a year ago.

Bruce Potter tells Brownfield pesticide applications are increasing, and it’s mostly the smaller fields that are reaching economic threshold.

He says aphids tend to like dryer conditions and certain soil types.

“There’s evidence that soils testing low in potassium tend to have a little big higher aphid populations.  Of course, that a lot of times ties in with soil moisture as well.  They tend to be the lighter textured soils.”

Potter continues to warn against treating for aphids before 80 percent of the plants are infested, and not just for economic reasons.

“A lot of guys want to go ahead and put that insecticide (on) and get it over with, but what happens is that the insecticides that we’re using right now are harmful to the predators (of aphids).  Those lady beetles (and) parasitic wasps out of the equation.”

He says eliminating predators may allow aphid populations to increase rapidly.

And Potter wants growers to stay vigilant in their scouting because within the last week a large number of winged aphids have been produced.