Though more of a curiosity, and infrequent, it is refreshing for us to receive calls/emails of mysterious insects “threatening” the crop.
Christian Krupke
As we move into the first days of summer, we are finished with the early season, migratory moths and caterpillars (armyworms, black cutworms) and are now into those that overwinter here. For those pheromone trapping for western bean cutworm moths, you should begin this week. This is just the beginning of an extended moth emergence and flight, with their peak activity expected 2-3 weeks from now. Those in high-risk areas, i.e., sandy soils, high moth flight and WBC history should be gearing up for field scouting of corn, even those with Bt-traits. Depending on the trait expressed by your corn hybrids, efficacy can be highly variable. Scouting of pre-tassel corn should begin once multiple moths are being captured regularly. In five different areas of a field, inspect 20 consecutive plants for egg masses which are laid on the upper surface of the top leaves of corn and/or larvae that may[Read More…]
Earlier this week, we received reports of armyworm in northern counties continuing to damage wheat.
Small, caterpillar-like larvae, often confused with armyworm, can occasionally be found in wheat and some other grassy cover crops. These are not caterpillars at all, but are sawfly larvae, likely grass sawfly (Pachynematus sp.). Adult sawflies are insects with four wings that are distant relatives of the honeybee. They can be thought of as primitive wasps, but they do not have a stinger. The larvae are usually plant feeders and a few are pests of home gardens (rose sawfly or the confusingly named pear slug, for example). The sighting of foliage feeding sawfly larvae in wheat fields is infrequent in the Midwest. And although this species feeds on the leaves, it is minor pest. This is more of a curiosity than anything else, and an opportunity to learn the differences between different insect larval types – always fun! Full size larvae, about 1.25 inches, may feed on stems causing head[Read More…]
Over the past six weeks, armyworm moth captures at the Purdue Ag Research Centers (see accompanying “Armyworm Pheromone Trap Report”) have been variable.
Could this be a cutworm year? Rainfall has delayed field work (e.g. weedy fields) and corn planting (i.e., lots of emerging corn).
Locally, we have been impressed with the number of black cutworm moths captured in our pheromone traps the last few weeks.
Over the past two weeks, armyworm moth captures at the Purdue Ag Research Centers (see accompanying “Armyworm Pheromone Trap Report”) have been variable, certainly not eye-popping!
For the last couple of weeks, storms originating in the Southwestern U.S. have effectively “vacuumed up” black cutworm (BCW) moths and deposited them, along with rainfall, in the Midwest.
Pest managers in southern Indiana should now be scouting their alfalfa for leaf feeding from weevil larva.
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