We’ve received questions about black, triangular moths flying around farms, homes, and yards, and especially to lights at night.
Christian Krupke
This is a wonderful time of the year in the Hoosier state, as we drive through the countryside, we are greeted with the pleasing sight of several colorful butterfly species gliding across and roads, near puddles of water, or on fall flowering plants.
Though Japanese beetle numbers and their defoliation to soybean typically get lots of mid-season attention, their pressures seemed to be lower this year.
Increasingly, we are getting inquires of swarms of “bee-like” flies around Indiana fields, farmsteads, and rural environments, and wanted to take the opportunity to tell you a bit about this curiosity.
Tracking the western bean cutworm moth flight wouldn’t be possible without the many pheromone trap cooperators in our network, see following “Western Bean Cutworm Pheromone Trap Report.”
The western bean cutworm (WBC) trapping season continues, and after a slow start, moth flights have rapidly increased in many northern Indiana county traps the past two weeks. With warm temperatures, egg development and hatch will happen within about 6-8 days after they are first placed by females. This will give little time for egg scouting. Unfortunately larval scouting is far more difficult, time-consuming and less reliable. In other words, some larvae have hatched and have already infested corn whorls, leaf axils, and/or ears. Control is very difficult at this point and those just looking for egg masses beginning now will likely be underestimating the population. However, it’s not too late! Although some eggs have hatched, our current period of increased moth activity represents the peak for egg-laying, as the vast majority of WBC eggs will be laid over the next 2 weeks. Use moth trap catches[Read More…]
Japanese beetle adults are emerging, though slowly, throughout the state.
Potato leafhopper populations have been increasing with the warming temperatures and dry weather in most areas of the state.
Pheromone trapping for western bean cutworm moths began this past week. Though typically not initially impressive (see “Western Bean Cutworm Pheromone Trap Report”) this is just the beginning of an extended moth emergence and flight, with peak activity expected 2-3 weeks from now. Those in high-risk areas, i.e., sandy soils, high moth flight, northern Indiana counties and western bean cutworm history, should be gearing up for field scouting of corn, even those with Bt-traits. Remember that WBC larvae are no longer susceptible to most of the Bt traits in our corn hybrids (including those in SmartStax hybrids) and therefore scouting, followed by timely insecticide sprays are really the only reliable control option for the vast majority of producers in the zone where this insect is common. This is principally the northern tier of counties in Indiana, extending into Michigan and parts of Ohio. Only Bt hybrids expressing the Vip3a toxin[Read More…]
Insecticide recommendations for controlling in-season infestations have been updated for corn, soybean and alfalfa.
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