“Choosing the best insecticide depends on crop, pest, pest pressure, and cost,” said Brad Hipsag, Federated agronomy sales rep at the Ogilvie location. Well-scouted fields make it possible to properly identify pests and assess the pressure from those pests. “Be sure to scout those fields,” he said.

“The economic threshold for soybeans aphids (see previous article) is 250 aphids per plant on 80% of the field,” said Hipsag, with “economic threshold” being defined as “the insect's population level or extent of crop damage at which the value of the crop destroyed exceeds the cost of controlling the pest.”

“Spraying below the economic threshold could have adverse effects, killing insects that are beneficial to the crop, and environment,” said Hipsag.  And, “unnecessary spraying could be a catalyst for insect resistance.”

The wide variety of insecticide groups – carbamates, organophosphates, pyrethroids, and neonicotinoids, to name a few – offer different active ingredients that point to what will be most effective and guard against resistance.

When pest/economic thresholds are reached, Federated recommends Warrior II with Zeon Technology® or Bifenture® EC for controlling or suppressing aphids and spider mites on soybeans; both insecticides are pyrethroids.

“Bifenture EC is going to be better on spider mites,” said Hipsag, whereas Warrior II is for suppression alone.

Warrior is also labeled for leafhopper and weevil control in alfalfa (Bifenture EC) is not. Always remember to read and follow label instructions.

Talk to your Federated Agronomist to discuss what’s best for your soybean crop this season and/or to set up custom spraying.