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Grain weevil Grain weevil size

Granary Weevil (Sitophilus granarius)

Description: Cylindrical, shiny red-brown to black body, about 1/13"-1/8" long; long head with distinct snout; ridged wing-covers, thorax marked with oval pits; flightless; cold tolerant

Life cycle: Minimum 28 days

Feeding habits: Adults feed on whole and broken kernels; larvae grow from eggs deposited inside kernels

Signs of infestation: Live adult weevils, and damaged grain with “shot hole” appearance.

Control tips: Clean and treat empty bins with Centynal™ Insecticide and Diacon® IGR; monitor grain throughout storage period; use grain protectants to help suppress insect populations; fumigate if grain is found to be infested upon receipt or shortly afterward; aerate grain during warm weather periods of storage to help control moisture and temperature.

Product recommendations: High rate of Diacon® IGR liquid, or Diacon-D® IGR, combined with Centynal™ EC Insecticide or 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.