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Lesser grain borer Lesser grain borer size

Lesser Grain Borer (Rhyzopertha dominica)

Description: Voracious feeders, 1/8” long, brown/black cylindrical bodies; head not visible from above; strong flier capable of rapidly spreading infestations; c-shaped white larva has small dark head, three pairs of small legs.

Life cycle: Variable based on temperature, minimum 25 days

Feeding habits: Adults and larvae bore into grain kernels, feed on whole grain or dust.

Signs of infestation: Live adult insects, fragmented kernels, and powdery residue; a sweet musty odor is associated with this insect. Damaged grain with “shot hole” appearance.

Control tips: Clean and spray grain bins with Diacon® IGR PLUS prior to grain storage. Inspect and treat incoming grain with Diacon® IGR or Diacon® IGR PLUS; monitor grain throughout storage period.

Product recommendations: Diacon® IGR, Centynal™ EC Insecticide, Diacon® IGR PLUS, Diacon®-D IGR, Pyronyl™ Crop Spray

Application tips: When treating flowing grain on belts or at transitions, 2 or more nozzles are recommended; during auger or conveyor cup application, fewer nozzles may be used; position nozzles for full coverage of grain stream; avoid spraying onto sides of auger boots. Calibrate protectant flow rate and check often to help ensure proper application. Use automated switches to turn chemical pumps on when there is grain in the system and turn off when no grain is present.