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.

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.

Overhead view of a Lesser Grain Borer. A Lesser Grain Borer against a ruler, it measures 1/8th of an inch.

Recommended Products

Diacon IGR Family Product Shot

Diacon® IGR

Diacon® IGR is approved virtually everywhere stored product insects are a problem. Diacon® IGR interrupts the life cycle, providing long-term control.

Centynal EC Insecticide

This stored grain insecticide can be used in empty grain bins/silos and on grain to knockdown weevils and other pests to prevent bugs in grain.
Diacon IGR Plus Family Product Shot

Diacon® IGR Plus

This stored grain insect control contains an adulticide and insect growth regulator for quality grain protection to help get rid of weevils and other pests.

Diacon®-D IGR

Diacon®-D IGR is a insect growth regulator, ready-to-use, dry formulation option for controlling insects at on-farm and off-premise storage sites.
Pyronyl Crop Spray Family Product Shot

Pyronyl Crop Spray

Pyronyl™ Crop Spray features a high ratio of active ingredients to synergist for the flushing and rapid knockdown of multiple stored product insects.